Sample analyzer and its components

ABSTRACT

A sample analyzer includes a liquid aspirator to be stuck into the closed container for aspirating a sample from a closed container; a preparing section for preparing an analysis sample using the aspirated sample; and an analyzing section for analyzing the prepared analysis sample; the liquid aspirator including an elongated pipe, the pipe having a liquid flow path extending therein and a plurality of communicating sections provided in an outer surface thereof, at least one of the communicating sections communicating between an inside and an outside of the container when the pipe is stuck into the container.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This application is related to Japanese Patent Application Nos.2002-334243 (filed on Nov. 18, 2002), 2002-334251 (filed on Nov. 18,2002), 2002-334272 (filed on Nov. 18, 2002), 2002-334286 (filed on Nov.18, 2002), 2002-334293 (filed on Nov. 18, 2002), and 2003-193715 (filedon Jul. 8, 2003) whose priorities are claimed under 35 USC § 119, thedisclosures of which are incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to a sample analyzer for analyzing a bloodsample, a urine sample and the like and its components used therein and,particularly, to a versatile and portable sample analyzer.

[0004] 2. Description of Related Art

[0005] Art hitherto known in relation to this invention is as follows.

[0006] A small-scale automatic analyzer comprising a reaction vesseldisk having a reaction table with its circumferential portionequidistantly divided into a plurality of portions, a plurality ofreaction vessels held by the reaction vessel disk, means fortransporting the respective reaction vessels to a sample dispenser, toan agent dispensing position and to an optically measuring position,means for sucking and dispensing a required amount of a sample into thereaction vessel, and means for optically analyzing the sample in thereaction vessel (see, for example, Japanese Unexamined PatentPublication No. 11-94842 (1999));

[0007] A pipette comprising a hollow pipe having an end sealed with aseal member, and a suction port provided in a side wall of the pipeadjacent in the vicinity of the end (see, for example, U.S. Pat. No.5,969,272); and

[0008] A pipette comprising a thin suction pipe for sucking a liquidsample, and a thin vent pipe for ventilation during the suction, thesuction pipe and the vent pipe being disposed in parallel (see, forexample, U.S. Pat. No. 5,969,272).

[0009] There have been proposed various types of blood analyzers foranalyzing samples, for example, blood. Most of the recent bloodanalyzers have a greater size and a higher operation speed to handle amultiplicity of samples in a short time. In addition, the operation ofthe blood analyzers is complicated, so that special operators should beemployed as regular staff. Local hospitals and private clinics which donot frequently need blood analyses currently commission a special bloodanalysis center to perform the blood analyses. However, it is impossibleto immediately obtain the results of blood analyses in an emergencycase. Therefore, there is a demand for a highly accurate,easy-to-operate and small-scale automatic blood analyzer.

[0010] Such a demand is applied to not only the blood analyzer but alsoa urine analyzer and the like.

[0011] In such a sample analyzer, it is preferred to employ a so-calledAD system (Autodilution system) in which the liquid sample is sucked andquantified by a suction device such as a syringe pump having a pipetteso that the analyzer may have a smaller scale with its more simplifiedconstruction. However, in the case of this system, when the pipette isinserted in a vacuum blood sampling tube (a rubber-capped tube) employedas a sample container, a negative pressure is liable to remain in thevacuum blood sampling tube. Accordingly, the sucking operation of thesuction device is not smoothly performed, resulting in erroneousquantification. Thus, there is a problem that the analysis of the samplecannot be performed accurately.

[0012] On the other hand, if a conventional vent pipe is attached to thepipette in parallel, the analyzer needs to further provide a cleaningflow system for cleaning the vent pipe, so that the construction of theanalyzer is complicated.

SUMMARY OF THE INVENTION

[0013] In view of the foregoing, it is an object of the presentinvention to simplify the operation of a sample analyzer for easyhandling of the analyzer by doctors and nurses, reduce the size andweight of the analyzer for easy transportation of the analyzer todiagnostic and medical treatment sites, suppress the noises of theanalyzer for a quiet environment, and ensure safe and easy maintenanceand inspection of the analyzer, and particularly obtain the highlyaccurate results of sample analyses even with the use of the analyzerhaving a simple construction.

[0014] The present invention provides a sample analyzer comprising: aliquid aspirator to be stuck into the closed container for aspirating asample from a closed container; a preparing section for preparing ananalysis sample using the aspirated sample; and an analyzing section foranalyzing the prepared analysis sample; the liquid aspirator includingan elongated pipe, the pipe having a liquid flow path extending thereinand a plurality of communicating sections provided in an outer surfacethereof, at least one of the communicating sections communicatingbetween an inside and an outside of the container when the pipe is stuckinto the container.

[0015] In accordance with one aspect of this invention, there isprovided a liquid aspirator for aspirating liquid from a closedcontainer, comprising: an elongated pipe having a liquid flow pathextending therein and a plurality of communicating sections; wherein thecommunicating sections are provided in an outer surface of the pipe forcommunicating between an inside and an outside of the container when thepipe is stuck into the container.

[0016] In accordance with another aspect of this invention, there isprovided a liquid aspirator for aspirating a liquid from a closedcontainer, comprising: an elongated pipe having a liquid flow pathextending therein and a head section tapered toward a tip thereof;wherein the tip is positioned on an axis of the pipe.

[0017] In accordance with further another aspect of this invention,there is provided a sample analyzer comprising; a preparing section forpreparing an analysis sample using a sample; an analyzing section foranalyzing the prepared analysis sample; first and second flow paths fortransporting liquid to the preparing section; first and second valvesfor opening and closing the first and second flow paths, respectively;first and second air bubble sensors for sensing an air bubble in thefirst and second flow paths, respectively, each air bubble sensoroutputting a signal; and a controller for controlling the first andsecond valves so that the valves are selectively opened, wherein thecontroller judges whether the air bubble is present in the flow pathopened by the valve based on the signals outputted from the first andsecond air bubble sensors.

[0018] In accordance with still another aspect of this invention, thereis provided an air bubble detector comprising: first and second airbubble sensors for sensing an air bubble in first and second flow paths,respectively, each air bubble sensor outputting a logical pulse signalsrepresenting a sensing time periods of the air bubbles in pulse width;and an integrating section for integrating pulse widths of the logicalpulse signals outputted from each sensor during a time period.

[0019] In accordance with still another aspect of this invention, thereis provided a sample analyzer comprising: an adaptor for holding asample container containing a sample; a rack for removably receiving theadaptor; a preparing section for preparing an analysis sample from thesample; and an analyzing section for analyzing the prepared analysissample; wherein the adaptor comprises a sample container supportingsection for receiving the sample container and a receiving tray forreceiving the sample to be spilled from the sample container.

[0020] In accordance with further another aspect of this invention,there is provided an adaptor which is removably inserted in a rack of asample analyzer to hold a sample container containing a sample,comprising: a sample container supporting section for receiving thesample container; and a receiving tray for receiving the sample to bespilled from the sample container.

[0021] In accordance with still another aspect of this invention, thereis provided a sample analyzer comprising: a preparing section forpreparing an analysis sample to be analyzed; and an analyzing sectionfor analyzing the prepared analysis sample, wherein the preparingsection comprises a syringe pump unit used for preparing the analysissample, the syringe pump unit including: a first syringe pump having afirst cylinder and a first piston to be inserted in the first cylinder;a second syringe pump having a second cylinder and a second piston to beinserted in the second cylinder; a connecting section provided betweenthe first syringe pump and the second syringe pump for connecting thefirst piston and the second piston; and a driving source for driving thefirst and second pistons through the connecting section.

[0022] In accordance with further another aspect of this invention,there is provided a syringe pump unit comprising: a first syringe pumpincluding a first cylinder and a first piston to be inserted in thefirst cylinder; a second syringe pump including a second cylinder and asecond piston to be inserted in the second cylinder; a connectingsection for connecting the first piston and the second piston; and adriving source for driving the first and second pistons through theconnecting section.

[0023] In accordance with still another aspect of this invention, thereis provided a sample analyzer comprising: a preparing section forpreparing an analysis sample to be analyzed using a sample, a firstliquid and a second liquid; and a detector for detecting a signal fromthe analysis sample, wherein the preparing section comprises a liquidtransfer unit, the liquid transfer unit including: a pump connected to afirst liquid retaining section for storing the first liquid and a secondliquid retaining section for storing the second liquid; a flow path forconnecting between the pump and the second liquid retaining section; athird liquid retaining section placed in the flow path; and a liquiddischarge section connected to the third liquid retaining section; thepump transporting the second liquid from the second liquid retainingsection to the third liquid retaining section and discharging the secondliquid with the first liquid via the liquid discharge section to thedetector.

[0024] In accordance with further another aspect of this invention,there is provided a liquid transfer unit comprising: a pump connected toa first liquid retaining section for storing a first liquid and a secondliquid retaining section for storing a second liquid; a flow path forconnecting between the pump and the second liquid retaining section; athird liquid retaining section placed in the flow path; and a liquiddischarge section connected to the third liquid retaining section; thepump transporting the second liquid from the second liquid retainingsection to the third liquid retaining section and discharging the secondliquid with the first liquid via the liquid discharge section.

[0025] These and other objects of the present application will becomemore readily apparent from the detailed description given hereinafter.However, it should be understood that the detailed description andspecific examples, while indicating preferred embodiments of theinvention, are given by way of illustration only, since various changesand modifications within the spirit and scope of the invention willbecome apparent to those skilled in the art from this detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 is a front perspective view of a blood analyzer accordingto this invention;

[0027]FIG. 2 is a rear perspective view of the blood analyzer accordingto this invention;

[0028]FIG. 3 is a perspective view of a container housing unit attachedto the blood analyzer according to this invention;

[0029]FIG. 4 is a front view of a sample setting section of the bloodanalyzer according to this invention;

[0030]FIG. 5 is a top surface view of an adaptor according to thisinvention;

[0031]FIG. 6 is a front view of the adaptor according to this invention;

[0032]FIG. 7 is a side view of the adaptor according to this invention;

[0033]FIG. 8 is a diagram for explaining a state where the adaptor isinserted into a sample rack according to this invention;

[0034]FIG. 9 is a diagram for explaining the operation of the samplesetting section of the blood analyzer according to this invention;

[0035]FIG. 10 is a diagram for explaining the operation of the samplesetting section of the blood analyzer according to this invention;

[0036]FIG. 11 is a diagram for explaining the operation of the samplesetting section of the blood analyzer according to this invention;

[0037]FIG. 12 is a front view of a detecting section of the bloodanalyzer according to this invention;

[0038]FIG. 13 is a front view of a pipette horizontally driving sectionof the blood analyzer according to this invention;

[0039]FIG. 14 is a front view of a pipette vertically sliding section ofthe blood analyzer according to this invention;

[0040]FIG. 15 is a view from a B-B arrow direction in FIG. 14;

[0041]FIG. 16 is a front view of the pipette vertically sliding sectionof the blood analyzer according to this invention;

[0042]FIG. 17 is a front view of major portions of the pipettevertically sliding section and the pipette horizontally driving sectionaccording to this invention;

[0043]FIG. 18 is a left side view of major portions of the pipettevertically sliding section and the pipette horizontally driving sectionaccording to this invention;

[0044]FIG. 19 is a left side view of a pipette vertically drivingsection according to this invention;

[0045]FIG. 20 is a view from a C-C arrow direction in FIG. 19;

[0046]FIG. 21 is a diagram for explaining the operation of the pipettevertically driving section according to this invention;

[0047]FIG. 22 is a diagram for explaining the operation of the pipettevertically driving section according to this invention;

[0048]FIG. 23 is a partly cut-away front view of major portions of adetector according to this invention;

[0049]FIG. 24 is a partly cut-away side view of major portions of thedetector according to this invention;

[0050]FIG. 25 is a top surface view of a mixing chamber according tothis invention;

[0051]FIG. 26 is a vertical sectional view of the mixing chamber shownin FIG. 25;

[0052]FIG. 27 is a vertical sectional view of a pipette according tothis invention;

[0053]FIG. 28 is a top surface view of a cleaner body according to thisinvention;

[0054]FIG. 29 is a view from a D-D arrow direction in FIG. 28;

[0055]FIG. 30 is a view from an E-E arrow direction in FIG. 28;

[0056]FIG. 31 is a diagram for explaining the operation of the cleanerbody according to this invention;

[0057]FIG. 32 is a diagram for explaining the operation of the cleanerbody according to this invention;

[0058]FIG. 33 is a diagram for explaining a positional relationshipbetween the cleaner body and the pipette shown in FIG. 28;

[0059]FIG. 34 is a vertical sectional view of another exemplary pipetteaccording to this invention;

[0060]FIG. 35 is an enlarged view of a major portion of the pipetteshown in FIG. 34;

[0061]FIG. 36 is an end view of the pipette shown in FIG. 35;

[0062]FIG. 37 is a view from an A-A arrow direction in FIG. 35;

[0063]FIG. 38 is a top surface view illustrating another exemplaryadaptor employed in the blood analyzer according to this invention;

[0064]FIG. 39 is a front view of the adaptor shown in FIG. 38;

[0065]FIG. 40 is a side view of the adaptor shown in FIG. 38;

[0066]FIG. 41 is a diagram for explaining a state where the adaptorshown in FIG. 38 is inserted into the sample rack according to thisinvention;

[0067]FIG. 42 is a fluid circuit diagram according to this invention;

[0068]FIG. 43 is an electrical circuit diagram according to thisinvention;

[0069]FIG. 44 is a flow chart illustrating the operation of the bloodanalyzer according to this invention;

[0070]FIG. 45 is a flow chart illustrating the operation of the bloodanalyzer according to this invention;

[0071]FIG. 46 is a flow chart illustrating the operation of the bloodanalyzer according to this invention;

[0072]FIG. 47 is a detailed diagram of major portions of the fluidcircuit according to this invention;

[0073]FIG. 48 is a front view of a syringe pump unit according to thisinvention;

[0074]FIG. 49 is a vertical sectional view of a syringe pump accordingto this invention;

[0075]FIG. 50 is a diagram for explaining the operation of majorportions of the syringe pump unit shown in FIG. 48;

[0076]FIG. 51 is a diagram for explaining the operation of the majorportions of the syringe pump unit shown in FIG. 48;

[0077]FIG. 52 is a diagram for explaining the operation of the majorportions of the syringe pump unit shown in FIG. 48;

[0078]FIG. 53 is a top surface view of an air bubble sensor according tothis invention;

[0079]FIG. 54 is a view from an A-A arrow direction in FIG. 53;

[0080]FIG. 55 is a signal processing circuit diagram for processingrespectively output signals from the air bubble sensors according tothis invention;

[0081]FIG. 56 is a timing chart illustrating the signals of the circuitshown in FIG. 55;

[0082]FIG. 57 is a timing chart illustrating the signals of the circuitshown in FIG. 55;

[0083]FIG. 58 is a circuit diagram illustrating another exemplary signalprocessing circuit;

[0084]FIG. 59 is a timing chart illustrating the signals of the circuitshown in FIG. 58;

[0085]FIG. 60 is a circuit diagram illustrating another exemplaryswitching circuit;

[0086]FIG. 61 is a top surface view illustrating further anotherexemplary adaptor employed in the blood analyzer according to thisinvention;

[0087]FIG. 62 is a front view of the adaptor shown in FIG. 61;

[0088]FIG. 63 is a view from an S-S arrow direction in FIG. 61;

[0089]FIG. 64 is a top surface view of a major portion of the adaptorshown in FIG. 61;

[0090]FIG. 65 is a view from a T-T arrow direction in FIG. 64;

[0091]FIG. 66 is a diagram for explaining a state where the adaptorshown in FIG. 61 is inserted into the sample rack;

[0092]FIG. 67 is a sectional view of a pipette according to anotherembodiment of this invention; and

[0093]FIG. 68 is a plan view of a major portion of the pipette shown inFIG. 67.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0094] A blood analyzer according to one embodiment of this inventionwill hereinafter be described as one example of a sample analyzer.

[0095] The blood analyzer according to this invention is preferablyautomated. The “automatic” blood analyzer herein means a blood analyzerwhich permits a user to set at least one sample vessel in the analyzer,and is capable of automatically detecting constituents of a blood samplecontained in the sample vessel, calculating values of analysis items,and outputting the results of the calculation.

[0096] The blood analyzer is adapted to analyze a blood sample of amammal such as a human.

[0097] Where the blood sample is a human blood sample, exemplaryanalysis items (measurement/analysis items) include the number of redblood cells (RBC), the number of white blood cells (WBC), the amount ofhemoglobin (HGB), the value of hematocrit (HCT), the number of platelets(PLT), a mean corpuscular volume (MCV), a mean corpuscular hemoglobin(MCH), and a mean corpuscular hemoglobin concentration (MCHC).

[0098] As for measurement principles, it is preferred to employ a sheathflow electrical resistance method for the measurement of the RBC and thePLT, an electrical resistance method for the measurement of the WBC, anda colorimetric method for the measurement of the HGB. The blood sampleto be analyzed is obtained by sampling blood from a subject into asample vessel (blood sampling tube). The blood sample may be a wholeblood sample or a sample preliminarily diluted to a predeterminedconcentration.

[0099] Particularly, where blood is sampled from an infant, the amountof the blood sample is small, so that the blood sample is preliminarilydiluted to a predetermined concentration (e.g., 26 times).

[0100] Usable as the sample vessel in the blood analyzer are commonvacuum blood sampling tubes (sealed with a rubber cap) and common openblood sampling tubes (having an open mouth) each having an outerdiameter of 12 to 15 mm and a length of not greater than 85 mm, andcontrol blood vessels each having an outer diameter of about 15 mm and alength of about 20 mm.

[0101] The amount of the blood sample required for the analysis is, forexample, 10 to 15 μL in the case of the whole blood sample, and 250 to350 μL in the case of the pre-diluted blood sample.

[0102] The blood analyzer comprises a main body and a container housingunit. Preferably, the main body is housed in a housing, and thecontainer housing unit is removably attached to a side wall of thehousing. The main body includes a display section provided on a frontupper portion of the housing. The display section includes an LCD(liquid crystal display panel) for displaying the results of theanalysis. If a touch panel for inputting analysis conditions is providedintegrally with the LCD, improvement in the operability of the analyzeras well as space saving can be achieved.

[0103] Disposed in the housing are: a sample setting section in whichthe user sets the sample vessel; a detecting section in which the sampleis quantitatively dispensed from the sample vessel and diluted and theblood constituents of the sample are detected; a fluid controllingsection including fluid controlling devices for controlling fluidsrequired for quantitatively dispensing and diluting the sample in thedetecting section; an electrical control board section which houseselectric components for electrically controlling the detecting section,the fluid controlling section and the display section; a power supplysection for transforming an AC voltage inputted from a commercial powersupply into a lower-level DC voltage; and a printer section for printingout the results of the analysis.

[0104] It is preferred to properly lay out these sections inconsideration of ease of operation and maintenance and heat generation.

[0105] Where the sample setting section is disposed in the vicinity of afront face of the housing and an opening/closing cover (sample settingpanel) is provided on the front face of the housing, for example, theuser can easily access the sample setting section to set the samplevessel in the sample setting section by opening the cover. Further, thesample vessel thus set is advantageously protected by the cover.

[0106] Where the detecting section is provided as a unit inward of aright or left side wall of the housing, for example, the detectingsection can easily be accessed for maintenance and inspection byremoving one side plate of the housing. The detecting section preferablyinclude a pipette driving device, a mixing chamber, and a detector forquantitatively dispensing the blood sample from the sample vessel bymeans of a pipette, properly diluting the blood sample and properlyanalyzing the blood constituents.

[0107] The pipette to be herein employed is a pipette generally referredto as “piercer” or “needle” having a sharp tip for piercing the cap ofthe sample vessel.

[0108] Where the fluid controlling section is disposed inward of theother side wall opposite to the detecting section or in back-to-backrelation with respect to the detecting section, the fluid controllingsection can easily be accessed for maintenance and inspection byremoving the other side plate of the housing.

[0109] Since electromagnetic valves and pumps provided in the fluidcontrolling section may cause noises, consideration is given to thesilencing of these components for reducing the noises (including suddennoises) of the entire fluid controlling section, for example, to a levelnot greater than 45 dB. Particularly, a pressure device such as anexternal compressor is not employed as a driving source for a fluidcircuit but, instead, a negative pressure pump is provided in thehousing for easy handling of the blood analyzer. The negative pressurepump, which serves as a negative pressure source, is frequently actuatedin the blood analyzer, requiring special consideration for the silencingthereof.

[0110] The power supply section includes components such as transistorsand diodes which generate heat. Therefore, the power supply section isdisposed in the uppermost portion of the housing, and ventilators (ventholes) are provided in the housing for spontaneous cooling of the powersupply. This arrangement obviates the need for provision of a fan forforcible cooling, and ensures silencing and space saving. With the powersupply section disposed in the uppermost portion, the other componentsare prevented from being adversely affected by the heat generated by thepower supply section.

[0111] Where the container housing unit is disposed in the side wall ofthe housing, the sample vessel can easily be replaced and the containerhousing unit can easily be connected to the analyzer body. The containerhousing unit is preferably adapted to house at least two containers forcontaining a diluent and a hemolyzing agent to be used in the analyzerbody, and a container for storing a waste liquid to be drained from theanalyzer body.

EXAMPLE

[0112] With reference to the attached drawings, this invention willhereinafter be described in detail by way of another embodiment thereof.However, it should be understood that the invention be not limitedthereto.

[0113]FIGS. 1 and 2 are a front perspective view and a rear perspectiveview, respectively, of a blood analyzer according to the embodiment ofthe invention.

[0114] As shown, an analyzer body 1 is housed in a housing 2, andincludes a display section 3 provided on a front upper portion of thehousing 2, a sample setting panel 4 provided on a lower front rightportion of the housing 2 and to be opened and closed when a samplevessel is set, and a button 5 to be pressed for opening the samplesetting panel 4.

[0115] A sample setting section 6 for receiving the sample vessel, and adetecting section 7 for quantitatively dispensing a sample from thesample vessel, diluting the sample and preparing an analysis sample areprovided inward of a right side plate of the housing 2.

[0116] A fluid controlling section 8 which collectively accommodatesfluid devices such as valves and pumps for controlling fluids for thequantitatively dispensing and dilution of the sample in the detectingsection 7 is provided inward of a left side plate of the housing 2. Anelectrical control board section 9 which accommodates a board mountedwith electrical control devices for electrically controlling thedetecting section 7, the fluid controlling section 8 and the displaysection 3 is provided inward of a rear side plate of the housing 2.

[0117] A power supply section 10 for transforming a commerciallyavailable AC voltage supplied thereto into a DC voltage, and a printersection 11 for printing out the results of the analysis are providedinward of a ceiling plate of the housing 2.

[0118] The right and left side plates, the rear side plate and theceiling plate are removably fastened by screws, so that the respectivesections are easily accessed for maintenance.

[0119] The power supply section 10 which includes a heat generatingcomponent is provided in the uppermost position within the housing 2,and ventilators (vent holes) 12, 13 are provided as surrounding thepower supply section 10 in the housing 2 as shown in FIG. 2. Therefore,air heated by the power supply section 10 is vented through theventilators 12, 13 for spontaneous air cooling without thermallyaffecting the other components of the analyzer. That is, the powersupply section 10 does not require forcible air cooling means such as acooling fan, so that the size reduction and noise reduction of theanalyzer can be achieved.

[0120] As shown in FIG. 3, a container housing unit 100 whichaccommodates containers 101, 103 respectively containing a diluent and ahemolyzing agent and a container 102 for storing waste liquid incombination is attached to a left side face of the analyzer body 1.

[0121] Construction and Operation of Sample Setting Section

[0122]FIG. 4 is a front view illustrating the construction of the samplesetting section 6. As shown, the sample setting panel 4 is supportedpivotally about a support shaft 14 in an arrow direction S, and biasedin the arrow direction S by a spring not shown. Above the sample settingpanel 4, the button 5 is supported pivotally about a support shaft 15and biased in an arrow direction T by a spring 16.

[0123] A claw 17 provided on an upper edge of the sample setting panel 4is engaged with a lower edge of the button 5 to prevent the samplesetting panel 4 from opening in the arrow direction S. The samplesetting panel 4 is provided with a cylindrical sample rack 18 forhousing the sample vessel.

[0124] As shown in FIG. 4, an adaptor detecting sensor(photo-interrupter) J1 and an adaptor recognizing sensor(photo-interrupter) J2 to be described later are provided in the samplesetting section 6.

[0125]FIGS. 5, 6 and 7 are a top surface view, a front view and a sideview, respectively, of an adaptor AD1 to be inserted preliminarily inthe sample rack 18 when the sample vessel (blood sampling tube) is setin the sample rack 18. As shown, the adaptor AD1 includes a cylindricalportion 20, which serves as a sample vessel supporting section, having acylindrical recess 19 to be engaged with a lower part of the samplevessel, and a receiving tray 22 provided around an inlet 29 of therecess 19 for receiving the sample to be spilled from the sample vessel.The receiving tray 22 is provided integrally with the cylindricalportion 20. One adaptor with the recess 19 having a depth of 45 mm andan inner diameter of 16.5 mm, and another adaptor with the recess 19having a depth of 45 mm and an inner diameter of 13.6 mm are prepared asthe adaptor AD1. Therefore, these adaptors can be employed for two typesof sample vessels having different outer diameters.

[0126] An identity piece 23 projecting upward from the receiving tray 22is provided in at a portion of the periphery of the receiving tray 22.The identity piece 23 is sensed by the adaptor detecting sensor(photo-interrupter) J1 (FIG. 4) for sensing simultaneously whether theadaptor AD1 is set in the sample rack and whether the sample settingpanel 4 is opened and closed.

[0127] An elongated projection 27 projecting downward from a lowersurface of the receiving tray 22 is provided on an outer surface of thecylindrical portion 20. When the adaptor AD1 is inserted in the samplerack 18 as shown in FIG. 8, the projection 27 is fitted into a notch 28(FIG. 4) of the sample rack 18 for positioning the adaptor AD1 withrespect to the sample rack 18. Whereby, the orientation of the receivingtray 22 is determined. In the above Example, the projection 27 may beprovided in the sample rack 18 and the notch 28 may be provided on theouter surface of the cylindrical portion 20.

[0128] After a user sets the adaptor AD1 with the recess 19corresponding to the size of the sample vessel SP1 in the sample rack 18as shown in FIG. 8, the user inserts the sample vessel SP1 into theadaptor AD1.

[0129]FIGS. 38, 39 and 40 are a top surface view, a front view and aside view, respectively, of an adaptor AD2 to be inserted preliminarilyin the sample rack 18 when a sample vessel containing controlled bloodconstituents for test (i.e., control blood) is set in the sample rack18. As shown, the adaptor AD2 includes a cylindrical portion 20 a, whichserves as a sample vessel supporting section, having a cylindricalrecess 19 a to be engaged with a lower part of the sample vesselemployed for the control blood, and a receiving tray 22 a providedaround an inlet 29 a of the recess 19 a for receiving the sample to bespilled from the control blood sample vessel. The receiving tray 22 a isprovided integrally with the cylindrical portion 20 a. One adaptor withthe recess 19 a having a depth of 15 mm and an inner diameter of 15.6 mmis prepared as the adaptor AD2. Therefore, this adaptor can be employedfor the control blood sample vessel.

[0130] An identity piece 23 a projecting upward from the receiving tray22 a is provided at an upper portion of the periphery of the receivingtray 22 a. The identity piece 23 a is sensed by the adaptor detectingsensor (photo-interrupter) J1 (FIG. 4) for sensing simultaneouslywhether the adaptor AD2 is set in the sample rack and whether the samplesetting panel 4 is opened and closed.

[0131] An elongated projection 27 a projecting downward from a lowersurface of the receiving tray 22 a is provided on an outer surface ofthe cylindrical portion 20 a. When the adaptor AD2 is inserted in thesample rack as shown in FIG. 41, the projection 27 a is fitted into thenotch 28 (FIG. 4) of the sample rack 18 for positioning the adaptor AD2with respect to the sample rack 18. Whereby, the orientation of thereceiving tray 22 a is determined.

[0132] An identity piece 23 b projecting downward from the receivingtray 22 a is provided at a lower portion of the periphery of thereceiving tray 22 a. The identity piece 23 b is sensed by an adaptorrecognizing sensor (photo-interrupt) J2 (FIG. 4) for recognizing that anadaptor inserted in the sample rack 18 is the adaptor AD2 for thecontrol blood sample vessel SP2.

[0133] After the user sets the adaptor AD2 with the recess 19 acorresponding to the size of the control blood sample vessel SP2 in thesample rack 18 as shown in FIG. 41, the user inserts the control bloodsample vessel SP2 into the adaptor AD2.

[0134]FIGS. 61 and 62 are a top surface view and a front view,respectively, of an adaptor AD3 employed for an open sample vesselhaving a small capacity in order to store a small-volume sample (blood)obtained from infants or small animals. FIG. 63 is a view from an S-Sarrow direction in FIG. 61.

[0135] The adaptor AD3 is preliminarily inserted in the sample rack 18when the sample vessel is set in the sample rack 18. The adaptor AD3supports resiliently the sample vessel thus set. Thus, when thesmall-volume sample is sucked from the vicinity of a bottom of thesample vessel by means of a pipette to be described later, the pipetteand the sample vessel are prevented from being damaged even if a tip ofthe pipette is brought into contact with the bottom of the samplevessel.

[0136] As shown, the adaptor AD3 includes a cylindrical portion 20 b,and a receiving tray 22 b provided around an upper opening of thecylindrical portion 20 b for receiving the sample to be spilled from thesample vessel. The receiving tray 22 b is provided integrally with thecylindrical portion 20 b.

[0137] As shown in FIG. 63, the cylindrical portion 20 b has acylindrical recess 19 b extending therein. A compression spring 42serving as a first resilient member is inserted into a bottom 41 of therecess 19 b, and a sample vessel inserting portion 43 with a recess 46for the sample vessel is mounted on the spring 42 for receiving a samplevessel SP3. A bottom 45 of the sample vessel inserting portion 43 andthe compression spring 42 are connected to each other by means of a pin44 piercing through the bottom 41, whereby the sample vessel insertingportion 43 is supported in the recess 19 b in a vertically slidablemanner. That is, when the sample vessel inserting portion 43 is presseddownward, the inserting portion 43 can be moved downward by the pressure(i.e. while working against the resilience of the compression spring42). The sample vessel supporting section is comprised of thecylindrical portion 20 b, the compression spring 42, the sample vesselinserting portion 43 and the pin 44.

[0138]FIG. 64 is a top surface view of the sample vessel insertingsection 43, and FIG. 65 is a view from a T-T arrow direction in FIG. 64.As shown, a flange 47 is provided at a periphery of an upper opening ofthe recess 46 in the sample vessel inserting section 43. A secondresilient member 48 for positioning the sample vessel SP3 coaxially withthe recess 46 is pressed by a ring-shaped holding board 49, and fastenedby two screws 40. The second resilient member 48 is composed of aring-shaped silicone rubber board and provided with four projectionpieces 48 a projecting toward the center of the opening.

[0139] A lower end portion of the recess 46 is conical in shape. Whenthe sample vessel SP3 is inserted into the recess 46, the sample vesselis pressed toward the center of the recess 46 by the resilience of theprojection pieces 48 a, and the recess 46 with the cone-shaped lower endportion allows the sample vessel SP3 to be guided toward the center ofthe recess. Thus, the sample vessel SP3 to be inserted into the recess46 is constantly positioned along the axis of the recess 46.

[0140] In the adaptor AD3, the sample vessel SP3 having an outerdiameter of 7.5 to 11 mm can be accommodated into the recess 46 having adepth of 21 mm. An identity piece 23 c projecting upward from thereceiving tray 22 b is provided at a portion of the periphery of thereceiving tray 22 b. The identity piece 23 c is sensed by the adaptordetecting sensor (photo-interrupter) J1 (FIG. 4) for sensingsimultaneously whether the adaptor AD3 is set in the sample rack andwhether the sample setting panel 4 is opened and closed.

[0141] An elongated projection 27 b projecting downward from a lowersurface of the receiving tray 22 b is provided on an outer surface ofthe cylindrical portion 20 b. When the adaptor AD3 is inserted in thesample rack 18 as shown in FIG. 66, the projection 27 b is fitted intothe notch 28 (FIG. 4) of the sample rack 18 for positioning the adaptorAD3 with respect to the sample rack 18. Whereby, the orientation of thereceiving tray 22 b is determined.

[0142] A pipette PTb with a flat tip as shown in FIGS. 67 and 68 issuitably employed to suck the small-volume sample from the bottom of thesample vessel SP3 when the adaptor AD3 is used. The pipette PTb will bedescribed later.

[0143] The adaptor AD1 having an inner diameter of 16.5 mm is molded bya transparent ABS resin, the adaptor AD1 having an inner diameter of13.6 mm is molded by a red ABS resin, the adaptor AD2 is molded by ablack ABS resin, and the adaptor AD3 is molded by a blue ABS resin.Thus, the adaptors AD1, AD2 and AD3 are discriminated by color, so thatthe user can select the type of the adaptors AD1, AD2 and AD3 and thesize of the sample vessels to be used. Also, different labels may beattached to the respective adaptors for the discrimination. In order toposition the adaptors, a projection may be provided in the sample rack18 and notches (recesses) may be provided in the respective adaptors.

[0144] In this arrangement, the button 5 is slightly pivoted in adirection opposite to the arrow direction T in FIG. 4 and the lower edgeof the button 5 is disengaged from the claw 17, when a user presses anupper end portion of the button 5. Thus, the sample setting panel 4 ispivoted about the support shaft 14 in the arrow direction S thereby tobe opened until a projection piece 4 a of the sample setting panel 4 isbrought into abutment against the support plate 21 as shown in FIG. 9.In this state, the user inserts the sample vessel SP1, SP2 or SP3 intothe sample rack 18 with the intervention of the adaptor AD1, AD2 or AD3as shown in FIG. 10.

[0145] When the sample setting panel 4 is thereafter closed as shown inFIG. 11, the sample vessel SP1 (or SP2, SP3) is held coaxially with thesample rack 18. The button 5 has a relatively large surface area (60mm×70 mm). Therefore, the user can operate the button 5 while holdingthe sample vessel.

[0146] Construction and Operation of Detecting Section

[0147] As shown in FIG. 12, the detecting section 7 includes a pipettehorizontally driving section 200, a pipette vertically sliding section300, a pipette vertically driving section 400, a mixing chamber 70 and adetector 50.

[0148] Pipette Horizontally Driving Section

[0149]FIG. 13 is a front view of the pipette horizontally drivingsection 200.

[0150] As shown, a driven pulley 202 and a driving pulley 203 arerotatably provided on a support plate 201, and a timing belt 204 isstretched between the pulleys 202 and 203. The driving pulley 203 isdriven by a pipette back and forth motor (stepping motor) 205 providedon the rear side of the support plate 201.

[0151] A guide rail 206 is provided horizontally on an upper portion ofthe support plate 201, and a guide shaft 207 is provided horizontally ona lower portion of the support plate 201. A vertically elongatedhorizontal movement plate 208 has an upper edge fitted on the guide rail206, a lower edge engaged with a sliding member 209 slidable along theguide shaft 207, and a coupling member 210 projecting from the rear sidethereof to be coupled with the timing belt 204. The horizontal movementplate 208 has screw holes 211, 212 for fixing the pipette verticallysliding member 300.

[0152] With this arrangement, the horizontal movement plate 208 ishorizontally movable by the driving of the motor 205. A pipette frontposition sensor (photo-interrupter) J5 for detecting the position of thehorizontal movement plate 208 is provided on the support plate 201.

[0153] Pipette Vertically Sliding Section

[0154]FIG. 14 is a front view of the pipette vertically sliding section300, and FIG. 15 is a view from a B-B arrow direction in FIG. 14. Asshown, the pipette vertically sliding section 300 includes a guide shaft302 vertically supported by a support member 301, and a pipette holder303 slidable on the guide shaft 302 with a pipette PT vertically heldtherein.

[0155] The support member 301 includes a longitudinally elongated guidegroove 304. A guide rod 305 horizontally projecting from the pipetteholder 303 is inserted in the guide groove 304 so as to be guided by theguide groove 304, whereby the pipette holder 303 can stably be slidvertically on the guide shaft 302. The support member 301 has notches306, 307 through which the screws extend for fixing the support member301 to the horizontal movement plate 208 shown in FIG. 13.

[0156] Further, the pipette holder 303 has a guide roller 308, which isengaged with a guide arm (to be described later) of the pipettevertically driving section 400 to cooperate with the guide arm formoving the pipette holder 303 vertically up and down.

[0157] A cleaner (pipette cleaning device) S in which the pipette PT isinserted for cleaning the exterior and interior of the pipette PT isprovided on a lower portion of the support member 301. When the pipetteholder 303 is located at the uppermost position of the support member301 (in a position shown in FIG. 14), a sharp distal tip of the pipettePT is inserted in the cleaner S.

[0158] Liquid supply/drain nipples 309, 310 and 311 fixed to a lowerportion of the support member 301 are connected to a proximal end of thepipette PT and ports of the cleaner S via tubes 312, 313 and 314,respectively.

[0159] A screw 315 fixed to the pipette holder 303 and a screw 316 fixedto a projection 317 of the support member 301 are provided for fixing aspacer plate 318 as shown in FIG. 16. The spacer 318 fixed as shown inFIG. 16 fixes the pipette holder 303 in the uppermost position of thesupport member 301 for preventing the sharp tip of the pipette PT frombeing withdrawn from the cleaner S.

[0160] The pipette vertically sliding section 300 is first rested on thehorizontal movement plate 208 shown in FIG. 13 with the spacer 318 fixedthereto and, after screws 319, 320 (FIG. 17) are screwed into the screwholes 211, 212 through the notches 306, 307, the spacer 318 is removedby unscrewing the screws 315,316. Thus, the pipette vertically slidingsection 300 can safely be mounted on the pipette horizontally drivingsection 200 with no possibility that the user is injured by the tip ofthe pipette PT. Where a trouble such as clogging occurs in the pipettePT, the pipette vertically sliding section 300 is entirely replaced. Atthis time, the spacer 318 is employed to safely perform a replacingoperation.

[0161]FIGS. 17 and 18 are a front view and a left side view,respectively, illustrating a state where the pipette vertically slidingsection 300 is mounted on the pipette horizontally driving section 200.As shown, an end 303 a of the pipette holder 303 of the pipettevertically sliding section 300 has a cross shape in section so as to beinserted in a main arm (to be described later) of the pipette verticallydriving section 400.

[0162] Pipette Vertically Driving Section

[0163]FIG. 19 is a left side view of the pipette vertically drivingsection 400, and FIG. 20 is a view from a C-C arrow direction in FIG.19.

[0164] As shown in FIG. 19, the pipette vertically driving section 400includes an elongated main arm 401 extending horizontally, a threadshaft 402 extending perpendicularly through the main arm 401 androtatably supported by a support plate 412, a nut 403 fixed to the mainarm 401 in threading engagement with the thread shaft 402, a slide rail404 a disposed parallel to the thread shaft 402 on the support plate412, a sliding member 404 b provided at a left end of the main arm 401in slidable engagement with the slide rail 404 a for vertically guidingthe main arm 401, and a pipette up and down motor (stepping motor) 405fixed to the support plate 412.

[0165] Pulleys 406 and 407 are fixed to an upper end of the thread shaft402 and an output shaft of the motor 405, respectively, and a timingbelt 408 is stretched between the pulleys 406 and 407. Therefore, themain arm 401 is movable vertically up and down by the driving of themotor 405. A pipette top position sensor J4 for sensing that the mainarm 401 reaches the uppermost position is provided on the support plate412.

[0166] A guide arm 409 is horizontally fixed to a right end of the mainarm 401 (is perpendicularly fixed to a paper) in engagement with theguide roller 308 of the pipette vertically sliding section 300 (FIG.18). The main arm 401 has a cross-shaped recess 410 provided in asurface thereof opposed to the cross-shaped end 303 a of the pipetteholder 303 (FIGS. 17 and 18). As shown in FIG. 20, the end 303 a of thepipette holder 303 is removably inserted in an arrow direction X intothe recess 410 with a proper clearance. In this case, a force for thevertical movement of the main arm 401 is directly transmitted to thepipette holder 303.

[0167] A lock rod 4 11 extends vertically through a middle portion ofthe main arm 401 with an upper end bent portion thereof in engagementwith the main arm 401. In this embodiment, the main arm 401 is composedof an aluminum alloy (A5052) and has a section of 20 mm×26 mm and alength of 108 mm. The guide arm 409 is prepared by folding a 0.5-mmthick steel plate (SECC) into an open square shape in section, and has alength of 180 mm.

[0168] Operations of Pipette Horizontally Driving Section, PipetteVertically Sliding Section and Pipette Vertically Driving Section

[0169] When the blood sample is quantitatively dispensed out of thesample vessel SP1 set in the sample rack 18 in the sample settingsection 6, the pipette back and forth motor 205 is driven to insert theend 303 a of the pipette holder 303 into the recess 410 of the main arm401 as shown in FIG. 20.

[0170] The pipette up and down motor 405 is driven to move up the mainarm 401 until the actuation of the pipette top position sensor J4 (FIGS.4 and 19). With the end 303 a is fitted in the recess 410, the centersof the thread shaft 402, the pipette PT and the sample vessel SP1 arepresent in the same plane, and a moment exerted on the pipette PT by thethread shaft 402 is minimized. Therefore, the torque of the motor 405 isefficiently converted into a pipette lowering force, when the pipette PTis lowered by the motor 405.

[0171] Then, the motor 405 is driven to lower the pipette PT through athrough-hole 26 a of a sample vessel lift preventing stopper 26 as shownin FIG. 21, and to allow the pipette PT to virtually reach the bottom ofthe sample vessel SP1 as shown in FIG. 22. Where the sample vessel SP1is a vacuum blood sampling tube with a rubber cap, it is necessary topiece the rubber cap with the tip of the pipette PT. Therefore, an inputelectric current greater than usual is supplied to the motor 405 from adriver circuit section (to be described later) to provide a greateroutput torque when the pipette PT is lowered to pierce through therubber cap.

[0172] When the pipette PT is lowered, the lock rod 411 is brought intoengagement with a lock hole 25 provided in a projection piece 24projecting inward of the sample setting panel 4 as shown in FIG. 22, sothat the pipette PT and the sample vessel SP1 are prevented from beingdamaged when the sample setting panel 4 is inadvertently opened. Wherethe sample vessel SP2 is set in the sample rack 18 with the interventionof the adaptor AD2 as shown in FIG. 41, the adaptor recognizing sensorJ2 is actuated. Therefore, a control section 500 to be described latercontrols a lowering distance of the pipette PT to allow the tip of thepipette PT to virtually reach the bottom of the sample vessel SP2.

[0173] In the state shown in FIG. 22, the pipette PT is employed forsampling the blood sample from the sample vessel SP1.

[0174] Upon completion of intake of the blood sample, the pipette PTreturns to the position shown in FIG. 21. Although there would be apossibility that the sample vessel SP1 along with the pipette PT islifted together with the rubber cap sticking thereto when the pipette PTis removed from the sample vessel SP1, the stopper 26 prevents therubber cap from being lifted together.

[0175] When the pipette PT is returned to the position shown in FIG. 21,the pipette back and forth motor 205 is driven to withdraw the end 303 aof the pipette holder 303 from the recess 410 of the main arm 401 in adirection opposite to the arrow direction X in FIG. 20, and then movethe pipette PT to an upper side of the mixing chamber 70 and thedetector 50 with the guide roller 308 rotated in contact with the innersurface of the guide arm 409. Then, the pipette up and down motor 405 isdriven, whereby a driving force thereof is transmitted to the pipetteholder 303 through the main arm 401, the guide arm 409 and the guideroller 308. Thus, the pipette PT is lowered and then lifted.

[0176] Construction of Detector

[0177]FIGS. 23 and 24 are a partly cut-away front view and a partlycut-away side view, respectively, of major portions of the detector 50.The detector 50 is composed of a transparent polysulfone resin. Asshown, the detector 50 includes first, second and third containerchambers 51, 52, 53 for containing liquids for the analysis. The firstcontainer chamber 51 has an upper portion open to the atmosphere. Thefirst container chamber 51 and the third container chamber 53communicate with each other.

[0178] A ruby orifice disk 54 is provided as a partition between thefirst container chamber 51 and the second container chamber 52, and thedisk 54 has an orifice 55 having a diameter of 80 μm. The secondcontainer chamber 52 is provided with a jet nozzle 56. The jet nozzle 56is supported by a nozzle support member 57 and a first electrode 58, andextends through the second container chamber 52 with its distal endfacing toward the orifice 55 and with its tail end communicating with aliquid supply nipple 59. The first electrode 58 is composed of astainless steel, and exposed to the inside of the second containerchamber 52.

[0179] The detector 50 further includes nozzles 60, 61 for supplying thediluent and the hemolyzing agent to the first container chamber 51,nipples 63, 64 for supplying and draining liquid into/from the secondcontainer chamber 52, and a liquid draining nipple 65 and an air bubbleinjecting nipple 66 provided in the bottom of the third containerchamber 53.

[0180] As shown in FIG. 24, the detector 50 further includes a secondplatinum electrode 67 projecting in the first container chamber 51, anda light emitting diode 68 and a photodiode 69 respectively disposed onopposite sides of the third container chamber 53. The light emittingdiode 68 emits light having a wavelength of 555 nm, and the photodiode69 detects the intensity of the light transmitting through the thirdcontainer chamber 53. The light emitting diode 68 and the photodiode 69are employed for measurement of a hemoglobin amount (HGB).

[0181] As will be described later, the first and third containerchambers 51, 53 are employed for preparation of a white blood cellmeasurement specimen, and the first and second container chambers 51, 52are employed for counting the numbers of the white blood cells, theplatelets and the red blood cells.

[0182] Construction of Mixing Chamber (Container for Mixing Liquids)

[0183]FIGS. 25 and 26 are a plan view and a vertical sectional view,respectively, of the mixing chamber 70. The mixing chamber 70 includes acontainer portion 71 for mixing the blood sample. The container portion71 has a cylindrical shape with its top open to the atmosphere. Adiluent supplying nipple 72 is provided in an upper portion of thecontainer portion 71. A nipple 73 for discharging a liquid mixture, anipple 74 for draining residual liquid from the container portion 71,and a nipple 75 for injecting air bubbles (air) for agitating the liquidin the container portion 71 are provided in the bottom of the containerportion 71.

[0184] The nipples 72, 73, 74, 75 are respectively connected to a liquidsupply port 72 a, liquid discharge ports 73 a, 74 a, and an air supplyport 75 a, which communicate with an interior surface of the containerportion 71. The liquid supply port 72 a opens so as to supply the liquidfrom the upper portion along the inner circumferential surface of thecontainer portion 71. Where the diluent is supplied into the mixingchamber 70 as will be described later for cleaning the chamber, theinterior surface of the container portion 71 is efficiently cleaned withthe diluent ejected from the liquid supply port 72 a.

[0185] The mixing chamber 70 is produced by injection-molding athermoplastic resin such as a polyether amide having a chemicalresistance. The interior surface of the container portion 71 has beenroughened to an arithmetic average surface roughness Ra of 0.29 μm so asto be imparted with a sufficiently high wettability with respect to thediluent. Therefore, the diluent injected from the liquid supply port 72a is supplied into the bottom of the container portion 71 withoutresiding as liquid drops on the interior surface, so that the bloodsample preliminarily supplied can accurately be diluted predeterminedtimes.

[0186] Constructions and Operations of Pipette and Cleaner (PipetteCleaning Device)

[0187]FIG. 27 is a vertical sectional view of the pipette PT. Thepipette PT is a stainless steel pipe, which has a suction flow path 31coaxially extending therein, and a distal tip sharply cut at an angle αof 30 degrees. Where the sample vessel SP1 with the cap is employed, thecap is pierced with the distal tip. A distal end of the suction flowpath 31 is sealed with a stainless steel seal 33, and a suction port 32is open in a side wall of the pipette PT with its axis extendingperpendicularly to the axis of the pipette PT.

[0188]FIG. 28 is a plan view of the cleaner body 80. FIGS. 29 and 30 areviews from a D-D arrow direction and from an E-E arrow direction,respectively in FIG. 28. As shown, a cleaner body 80 has a pipettethrough-hole 81 centrally extending therethrough, so that the pipette PTis vertically inserted in the pipette through-hole 81 from an inlet 81 ato an outlet 81 b. The pipette through-hole 81 has a round crosssection.

[0189] The pipette through-hole 81 includes a pipette guide hole 82, afirst through-hole 83 and a second through-hole 84 serially andcoaxially disposed in this order from the inlet 81 a to the outlet 81 b.The pipette guide hole 82 has an inner diameter slightly greater thanthe outer diameter of the pipette PT, and serves to guide the pipette PTso as to align the axis of the pipette PT with the axes of the first andsecond through-holes 83, 84.

[0190] On the other hand, the first and second through-holes 83, 84constitute a pipette cleaning hole for cleaning the pipette. A firstopening 85 a and a second opening 85 b are formed in the first andsecond through holes 83, 84, respectively.

[0191] The cleaner body 80 includes a cleaning liquid drain path 87 aallowing communication between the first opening 85 a and a cleaningliquid draining nipple 87, and a cleaning liquid supply path 88 aallowing communication between the second opening 85 b and a cleaningliquid supplying nipple 88.

[0192] The pipette guide hole 82, the first through-hole 83 and thesecond through-hole 84 respectively have inner diameters D1, D2 and D3which are set at 105%, 115% and 200% of the outer diameter of thepipette PT. Where the pipette PT has an outer diameter of 2.0 mm, forexample, D1=2.1 mm, D2=2.3 mm and D3=4.0 mm.

[0193] When the cleaning liquid (the diluent in this embodiment) issupplied from the nipple 88 into the second through-hole 84 and suckedfrom the nipple 87 with the pipette PT extending from the upper side tothe lower side through the pipette through-hole 81 as shown in FIG. 31,the cleaning liquid flows in uniform contact with the exterior of thepipette PT from the second through-hole 84 into the first through-hole83, and drained from the nipple 87.

[0194] Therefore, when the pipette PT is moved up in the arrow directionZ in this state, the blood sample and the like adhering on the exterior(outer circumferential surface) of the pipette PT is washed away withthe cleaning liquid and drained.

[0195] When the cleaning liquid flows into the nipple 87 from the nipple88, the distal suction port 32 with the tip of the pipette PT is keptwithin the first through-hole 83 a as shown in FIG. 32. When thecleaning liquid is supplied from the proximal end of the pipette PT tothe distal suction port 32 with the tip of the pipette PT, the cleaningliquid having passed through the suction flow path 31 of the pipette PTis drained from the suction port 32 of the pipette PT, and sucked intothe nipple 87 through the first opening 85 a but not drained into thesecond through-hole 84. Thus, the interior of the pipette PT (i.e., theinner surfaces of the suction flow path 31 and the suction port 32 ofthe pipette PT) is cleaned.

[0196] A positional relationship between the cleaner body 80 and thepipette PT as seen axially of the pipette PT is shown in FIG. 33. Asshown, the pipette PT is positioned with respect to the cleaner body 80with the axis of the suction port 32 and the axis of the opening 85 b ofthe cleaning liquid drain path 87 a forming an angle θ of greater than90 degrees. This is because the following phenomena have experimentallybeen observed.

[0197] (1) If θ≦90 degrees, the diluent (to be described later) filledin the suction flow path 31 and the suction port 32 of the pipette PT issucked out by the negative pressure in the cleaning liquid drain path 87a and a void occurs in the suction port 32 when the exterior or interiorof the pipette PT is cleaned. Therefore, the blood sample is introducedinto the void in the suction port 32 before the blood sample is suckedto be quantified by means of the pipette PT. Accordingly, the bloodsample is sucked into the pipette PT in an amount greater by thepreviously introduced amount than an intended amount, resulting inerroneous quantifying.

[0198] (2) If θ>90 degrees, the negative pressure in the cleaning liquiddrain path 87 a exerts no direct effect on the suction port 32.Therefore, accurate quantifying can be ensured because no void occurs inthe suction port 32 when the exterior or interior of the pipette PT iscleaned.

[0199] Another Exemplary Pipette

[0200]FIG. 34 is a side view illustrating another exemplary pipette PTato be suitably employed instead of the pipette PT (FIG. 27) where avacuum blood sampling tube (sealed with a rubber cap) is particularlyused as the sample vessel SP1, and FIG. 35 is an enlarged view of amajor portion of FIG. 34, FIG. 36 is an end view of the pipette PTa, andFIG. 37 is a view from an A-A arrow direction in FIG. 35.

[0201] As shown, the pipette PTa is a stainless steel pipe having anouter diameter of 1.5 mm, which has a suction flow path (fluid path) 31a having an inner diameter of 0.5 mm centrally extending therein. Asharp pyramidal portion (head) 37 having a trigonal pyramid shapetapered toward an apex T is formed at a distal end of the pipette PTa asshown in FIGS. 34 and 35. The apex T is positioned on the central axisof the pipette PTa as shown in FIG. 36. With this construction, alowering force of the pipette PTa is concentrated at the apex T, wherebythe rubber cap of the sample vessel SP1 is easily pierced with thepipette PTa. The pyramidal portion 37 may have a conical shape or aquadrangular pyramid shape. The rubber cap through which the pipette PTapierces has a thickness of about 5 mm.

[0202] The suction flow path 31 a has a distal end portion sealed with astainless steel seal as in that of the pipette PT of FIG. 27. Thepipette PTa has a suction port 32 a (FIG. 35) open in a side wallthereof. The suction port 32 a has an axis extending perpendicularly tothe axis of the pipette PTa, and communicates with the suction flow path31 a (FIG. 35).

[0203] Further, the pipette PTa has three elongated recesses 34, 35 and36 each having a groove shape provided in an outer surface thereof asextending in line parallel to the axis thereof as shown in FIG. 34. Thepyramidal portion 37 has a length L1 of 4 mm, the recesses 34, 35 and 36have lengths L2, L4 and L6 of 25 mm, 20 mm and 30 mm, respectively. Aninterval L3 between the recesses 34 and 35 is 5 mm, and an interval L5between the recesses 35 and 36 is 5 mm. From the viewpoint of reductionin production costs, it is preferred that the recesses 34, 35 and 36 areprovided in line parallel to the axis of the pipette PTa. However, therecesses may be provided in two or three lines parallel to the axis ofthe pipette PTa or may be provided in an outer surface of the pipettePTa as extending spirally thereof.

[0204] After the distal end of the pipette PTa is lowered to piercethrough the rubber cap, the recess 34 serves to let the internalpressure of the sample vessel back to the atmospheric pressureimmediately. When the pipette PTa is kept lowering, a part of the rubbercap goes into the recess 34, and then is pushed out through the intervalportion L3 of the pipette PTa.

[0205] When the pipette PTa is further lowered, the part of the rubbercap goes into the recess 35 and is pushed out through the intervalportion L5 of the pipette PTa, so that a through-hole is enlarged. Whena distal tip of the pipette PTa virtually reaches the bottom of thesample vessel SP1 and the recess 36 is disposed opposedly to the rubbercap, the part of the rubber cap does not go into the recess 36.Accordingly, the recess 36 serves to define an air hole through therubber cap, and the sample vessel SP1 has an inside open to theatmosphere via the air hole to a sufficient degree. Thus, the sample(blood) is sucked smoothly from the sample vessel SP1 by means of thepipette PTa.

[0206] The three elongated recesses 34, 35 and 36 are arranged in astraight line extending along the axis of the pipe from one ridgeline ofthe trigonal pyramid formed at the distal end of the pipette PTa asshown in FIG. 36. With this construction, the rubber cap is split by thepipette PTa with its ridgeline portions of the trigonal pyramid afterbeing pierced with the pipette PTa, and the recess 36 is disposedopposedly to one of the split portions of the rubber cap. Thus, therecess 36 can define the air hole through the rubber cap moreeffectively.

[0207] The exterior of the pipette PTa is cleaned by the cleaner S as inthat of the pipette PT. At the same time, the recesses 34, 35 and 36 arecleaned in this manner. As a result, there is no need to provide anothercleaner in the analyzer for cleaning only the recesses 34, 35 and 36.

[0208]FIGS. 67 and 68 are a sectional view of a pipette PTb and a planeview of a distal end thereof, respectively, according to anotherembodiment of this invention. The pipette PTb is employed suitably tosuck a small-volume sample from the vicinity of a bottom of anupper-open sample vessel having a small capacity for storing thesmall-volume sample.

[0209] As shown, the pipette PTb is composed of a stainless steel pipehaving an outer diameter of 1.5 mm, which has a suction flow path 31 bhaving an inner diameter 0.6 mm coaxially extending therein. The pipettePTb has a distal end with round portions having a radius of 0.4 mm andwith a groove 32 b crossing diametrically over the distal end. The widthof the groove 32 b is the same as the diameter of the suction flow path31 b, and the depth of the groove 32 b is 0.3 mm. With such a distal endshape, the distal end of the pipette PTb is brought into contact withthe bottom of the sample vessel to suck up the sample, and then thesample is sucked into the suction flow path 31 b through the groove 32b.

[0210] Constructions of Fluid Circuit and Electrical Circuit

[0211]FIG. 42 is a system diagram illustrating a fluid circuit accordingto the embodiment of the invention. In the fluid circuit, the pipettePT, the cleaner S, the mix chamber 70, the detector 50, a negativepressure pump P1, a liquid draining pump P2, an air pump P3, syringepumps SR1, SR2, SR4, a diluent chamber SC1, a hemolyzing agent chamberSC2, a waste liquid chamber WC, the diluent container 101, the wasteliquid container 102, the hemolyzing agent container 103, air bubblesensors BS1, BS2, and valves SV1 to SV16, SV18 to SV20 and SV23 to SV 28are connected by fluid supply tubes (flow paths). The syringe pumps SR1,SR4 are driven by a syringe pump motor STM4, and the syringe pump SR2 isdriven by a syringe pump motor STM5. Stepping motors may be employed asthe syringe pump motors STM4, STM5. The syringe pumps SR1, SR4 and thesyringe pump motor STM4 are integrated as a syringe pump unit PU (seeFIG. 48).

[0212] A preferred example of the diluent is CELLPACK available formSysmex Corporation, and a preferred example of the hemolyzing agent isSTROMATOLYSER WH available from Sysmex Corporation.

[0213]FIG. 43 is a block diagram illustrating the electrical circuitaccording to the embodiment of the invention. The power supply section10 transforms a voltage supplied from a commercial AC power supply intoa DC voltage (12V), which is supplied to the control section 500 and thedriver circuit section 501. The control section 500 is comprised of amicroprocessor including a CPU, a ROM and a RAM, and the driver circuitsection 501 includes driver circuits and I/O ports.

[0214] The driver circuit section 501 performs A-D conversion on outputsignals of the adaptor detecting sensor J1, the adaptor recognizingsensor J2, the pipette top position sensor J4, the pipette frontposition sensor J5, a pressure sensor J6 for detecting the negativepressure in the waste liquid chamber WC, a float switch J7 for detectinga liquid amount accumulated in the waste liquid chamber WC, the airbubble sensors BS1 and BS2, a hemoglobin detecting section 502 forallowing the light emitting diode 68 to emit light and for receiving anoutput from the photodiode 69, and a resistance-type detecting section503 for detecting a change in impedance between the electrodes 58 and 67through which a DC constant current passes, and outputs convertedsignals to the control section 500.

[0215] The control section 500 receives output signals from the drivercircuit section 501 and output signals from the touch panel 3 b, andprocesses these signals thus received according to a predeterminedprocessing program. The control section 500 causes the driver circuitsection 501 to drive the pipette up and down motor 405, the pipette backand forth motor 205, the syringe pump motors STM4, STM5, the negativepressure pump P1, the liquid draining pump P2, the air pump P3 and theelectromagnetic valves SV1 to SV16, SV18 to SV20 and SV3 to SV28 on thebasis of the results of the processing. Then, the control section 500controls the liquid crystal display 3 a of the display section 3 and theprinter section 11 to display and print out analysis conditions,analysis items, analysis results and the like.

[0216] Analytic Operation to be Performed by Blood Analyzer

[0217] An analytic operation to be performed by the blood analyzer shownin FIG. 1 will hereinafter be described with reference to the fluidcircuit shown in FIG. 42 and a flow chart shown in FIG. 44.

[0218] As shown in FIG. 44, when the power supply to the blood analyzeris turned on (Step S1), a diluent required for preliminary cleaning istransported from the container 101 into the diluent chamber SC1 (Step S1a). Then, when a measurement preparation period required for preparatoryoperations for the analysis including the preliminary cleaning operationis elapsed (Step S2), the diluent and hemolyzing agent required forpreparation of an analysis sample are transported from the containers101 and 103 into the diluent camber SC1 and the hemolyzing agent chamberSC2, respectively (Steps S2 a, S2 b), and a message “Ready” is displayedon the liquid crystal display 3 a of the display section 3.

[0219] Then, the user sets the sample vessel SP1 (or SP2, SP3) in thesample setting section 6 (FIG. 4) Step S4). Where a sample in the samplevessel thus set is a whole blood sample, the user selects a whole bloodmode by means of the touch panel 3 b of the display section 3 and, wherethe sample is a diluted sample, the user selects a pre-diluted mode(Step S5).

[0220] Then, the user presses a start button on the touch panel 3 b(Step S6). Where the sample vessel SP1 (or SP2, SP3) is not set and/orthe sample setting panel 4 is not closed in Step S4, the sensor J1detects such a situation, so that the analyzer does not operate. Wherethe sample vessel SP1 (or SP2, SP3) is set and the sample setting panel4 is closed, the analyzer starts operating. Where the whole blood modeis selected (Step S7), a specimen for measurement of the number of redblood cells (RBC) and a specimen for measurement of the number of whiteblood cells (WBC) are prepared from the whole blood sample (Steps S8,S9).

[0221] With the use of the WBC measurement specimen prepared in Step S9,measurement of the WBC and the amount of hemoglobin (HGB) is performed(Step S10), and then the measured WBC and HGB are displayed on theliquid crystal display 3 a (Step S11). Subsequently, measurement of theRBC is performed with the use of the RBC measurement specimen preparedin Step S8, and the number of platelets (PLT), a hematocrit value (HCT)and other analysis items are calculated. Then, the measured RBC and thecalculated values for the respective analysis items are displayed on theliquid crystal display (Steps S13, S14).

[0222] The WBC, the RBC and the PLT are determined by counting pulsesindicative of changes in impedance between the electrodes 58 and 67 ofthe detector 50. The HGB is determined by comparing the absorbance(blank level) of the diluent alone and the absorbance of the WBCmeasurement specimen measured by the photodiode 68. The HCT isdetermined on the basis of a maximum level of the pulses indicative ofthe changes in impedance between the electrodes 58 and 67, a meancorpuscular volume (MCV), a mean corpuscular hemoglobin (MCH) and a meancorpuscular hemoglobin concentration (MCHC) are calculated from thefollowing expressions:

[0223] MCV=(HCT)/(RBC)

[0224] MCH=(HGB)/(RBC)

[0225] MCHC=(HGB)/(HCT)

[0226] Then, a fluid circuit cleaning operation is performed. Uponcompletion of the cleaning operation (Step S15), the diluent and thehemolyzing agent are transported from the containers 101 and 103 to thechambers SC1 and SC2, respectively on standby for the analysis of thenext sample (Steps S18, S19), the routine returns to Step S3, and“Ready” is displayed on the liquid crystal display 3 a on standby forthe analysis of the next sample. Where the pre-diluted mode is selectedin Step S7, the RBC measurement specimen and the WBC measurementspecimen are prepared from a pre-diluted blood sample (Steps S16, S17).In this case, the pre-diluted sample is obtained by preliminarilydiluting a whole blood sample. Therefore, a preliminary dilution factorshould be taken into account so that the RBC measurement specimen andthe WBC measurement specimen have the same dilution factors as thoseprepared from the whole blood sample in the whole blood mode.

[0227] Next, operations to be performed in FIG. 44 (Steps) will bedescribed in detail with reference to the flow system diagram shown inFIG. 42. The analyzer is of a normally-closed valve type in which allthe valves in the fluid circuit are usually closed.

[0228] Diluent Transporting Operation (Steps S1 a, S2 a, S18) p As shownin the flow chart of FIG. 45, when the valve SV13 is opened (Step S21),a negative pressure is applied to the waste liquid chamber WC from thenegative pressure pump P1. Whereby, the diluent is supplied into thediluent chamber SC1 from the diluent container 101 through the airbubble sensor BS1. Where the air bubble sensor BS1 does not detect morethan a predetermined amount of air bubbles in a flow path (Step S22),the valve S13 is closed after the lapse of a predetermined time period(Steps S23, S24). Thus, a predetermined amount of the diluent is storedin the diluent chamber SC1.

[0229] On the other hand, where the air bubble sensor BS1 detects morethan the predetermined amount of the air bubbles in the flow path inSteps S22, the control section 500 judges that no diluent is present inthe diluent container 101. The valve 13 is thereafter closed, and thedisplay section 3 displays the judgment on the display 3 a (Steps S25,S26).

[0230] The user replenishes the diluent container 101 with the diluentor replaces the diluent container 101 with a new one (Step S27), andpresses a “diluent replenishing completion” button on the touch panel 3b of the display section 3 (Step S28). Whereby, the routine returns toStep S21.

[0231] Hemolyzing Agent Transporting Operation (Steps S2 b, S19)

[0232] As shown in the flow chart of FIG. 46, when the valve SV9 isopened (Step S31), a negative pressure is applied to the waste liquidchamber WC from the negative pressure pump P1, whereby the hemolyzingagent is supplied into the hemolyzing chamber SC2 from the hemolyzingcontainer 103 through the air bubble sensor BS2. Where the air bubblesensor BS2 does not detect more than a predetermined amount of airbubbles in a flow path (Step S32), the valve SV9 is closed after thelapse of a predetermined time period (Steps S33, S34). Thus, apredetermined amount of the hemolyzing agent is stored in the hemolyzingagent chamber SC2.

[0233] On the other hand, where the air bubble BS2 detects more than thepredetermined amount of the air bubbles in the flow path in Step S32,the control section 500 judges that no hemolyzing agent is present inthe hemolyzing agent container 103. The valve SV9 is thereafter closed,and the display section 3 displays the judgment the hemolyzing agent onthe display 3 a (Steps S35, S36).

[0234] The user replenishes the hemolyzing agent container 103 with thehemolyzing agent or replaces the hemolyzing agent container 103 with anew one (Step S37), and presses a “hemolyzing agent replenishingcompletion” button on the touch panel 3 b of the display section 3 (StepS38). Whereby, the routine returns to Step S31. Incidentally, thediluent transporting operation (Steps S1 a, S2 a, S18) and thehemolyzing agent transporting operation (Steps S2 b, S19) are notsimultaneously performed. That is, either of the operations isperformed.

[0235] Preliminary Cleaning Operation (Step S2)

[0236] (1) The pipette PT is moved to the upper side of the sample rack18, and then lowered as shown in FIG. 22. (At this time, the samplevessel SP1 is not set in the sample setting section 6.) Then, the valveSV19 is opened to suck the diluent from the diluent chamber SC1 into thesyringe pump SR2, and the valve SV19 is closed.

[0237] (2) The valves SV4, SV11, SV20 are opened, and the diluent issupplied into the cleaner S from the syringe pump SR2 and then drainedinto the waste liquid chamber WC. At the same time, the pipette PT islifted, and the cleaning of the exterior of the pipette PT is performed.When the tip of the pipette PT is inserted into the main body 80 of thecleaner S, the pipette PT is stopped. Thus, the cleaning of the exteriorof the pipette PT is completed.

[0238] (3) With the valves SV4, SV11, SV20 kept open, the pipette PT isheld at the position shown in FIG. 32. Then, the valves SV7 is opened,and the diluent is supplied into the pipette PT from the syringe pumpSR2 through the syringe pump SR1. At the same time, the diluentdischarged from the suction port 32 of the pipette PT is drained intothe waste liquid chamber WC for cleaning the interior of the pipette PT.

[0239] (4) When the valves SV7 is closed, the flow of the diluent fromthe suction port 32 of the pipette PT to the first opening 85 a isstopped, whereby the interior cleaning is completed. At this time, thesuction flow path 31 and the suction port 32 are filled with thediluent. On the other hand, the flow of the diluent from the secondopening 85 b to the first opening 85 a is continued and, when the valvesSV4, SV11, SV20 are closed, the flow is stopped. Therefore, the suctionport 32 of the pipette PT is kept filled with the diluent.

[0240] Preparation of RBC Measurement Specimen (Step S8)

[0241] (1) A negative pressure is applied to the waste liquid chamber WCfrom the negative pressure pump P1, and the valves SV14, SV10 areopened, whereby residual liquid is expelled from the detector 50 and themixing chamber 70. Thereafter, the valves SV14, SV10 are closed.

[0242] (2) The valve SV19 is opened, and the syringe pump SR2 isoperated for suction, whereby the diluent is sucked into the syringepump SR2 from the diluent chamber SC1. Then, the valve SV19 is closed.

[0243] (3) The pipette PT is lowered to be inserted into the samplevessel SP1 (FIG. 22). Then, the syringe pump SR1 is operated forsuction, whereby the pipette PT sucks a predetermined amount (10 μL) ofthe blood sample.

[0244] (4) Then, the pipette PT is lifted. During the lifting, thevalves SV4, SV20, SV11 are opened, whereby the diluent is supplied intothe cleaner S from the syringe pump SR2 and drained into the wasteliquid chamber WC for cleaning the exterior of the pipette PT. Then, thevalves SV4, SV20, SV11 are closed.

[0245] (5) The valves SV16, SV20 are opened, and the syringe pump SR2 isoperated for discharge, whereby a predetermined amount (1.3 mL) of thediluent is supplied into the mixing chamber 70. Then, the valves SV16,SV20 are closed.

[0246] (6) The pipette PT is moved to a position just above the mixingchamber 70, and lowered. Then, the syringe pump SR1 is operated fordischarge, whereby the 10-μL blood sample preliminarily sucked into thepipette PT is discharged into the mixing chamber 70. Thus, the bloodsample is diluted 130 times in the mixing chamber 70 through first-stagedilution, so that a 1.3-mL diluted sample is prepared in the mixingchamber 70.

[0247] (7) While the exterior of the pipette PT is cleaned as describedabove, the pipette PT is lifted. When the tip of the pipette PT isinserted into the main body 80 of the cleaner S, the valves SV7, SV20,SV11 are opened. Thereafter, the diluent is supplied into the pipette PTfrom the syringe pump SR2 through the syringe pump SR1 and drained intothe waste liquid chamber WC from the tip of the pipette PT for cleaningthe interior (inner surface) of the pipette PT. Then, the valves SV11,SV7, SV20 are closed.

[0248] (8) The valve SV6 is opened, and the air pump P3 is driven tosupply air into the mixing chamber 70, whereby the diluted sample isagitated in the mixing chamber 70 by air bubbles. Then, the air pump P3is stopped and the valve SV6 is closed.

[0249] (9) The pipette PT is lowered again into the mixing chamber 70.Then, the valves SV7, SV20 are opened, and the syringe pump SR2 isoperated for suction, whereby a predetermined amount (0.59 mL) of thefirst-stage diluted sample is sucked into the pipette PT. Then, thevalves SV7, SV20 are closed. Here, the diluent supplied from the syringepump SR2 into the pipette PT passes through the syringe pump SR1. Whenthe syringe pump SR2 is operated for suction and discharge of thediluent in the pipette PT, the diluent passes through the syringe pumpSR1. The same step is performed for all procedures described below.

[0250] (10) While the exterior of the pipette PT is cleaned as in Step(2) of the preliminary cleaning operation, the pipette PT is lifted.

[0251] (11) The valve SV14 is opened. Then, a negative pressure isapplied to the waste liquid chamber WC from the negative pressure pumpP1, whereby the residual sample in the mixing chamber 70 is drained intothe waste liquid chamber WC. Then, the valve SV14 is closed.

[0252] (12) The valves SV16, SV20 are opened, and the syringe pump SR2is operated for discharge, whereby the diluent is supplied into themixing chamber 70 from the syringe pump SR2. Thereafter, the valvesSV16, SV20 are closed. Then, the above Step (11) is performed again.Thus, the mixing chamber 70 is cleaned.

[0253] (13) The valves SV16, SV20 are opened, and the syringe pump SR2is operated for discharge, whereby a predetermined amount of the diluentis preliminarily dispensed in the mixing chamber 70 from the syringepump SR2. Then, the valves SV16, SV20 are closed.

[0254] (14) The pipette PT is lowered. Then, the valves SV7, SV20 areopened, and the syringe pump SR2 is operated for discharge, whereby 0.2mL out of the 0.59-mL first-stage diluted sample retained in the pipettePT is discharged into the mixing chamber 70. Then, the valves SV7, SV20are closed. Thereafter, the pipette PT is lifted. During the lifting,the exterior of the pipette PT is cleaned in the aforesaid manner.

[0255] (15) The valves SV16, SV20 are opened, and the syringe pump SR2is operated for discharge, whereby the diluent is supplied into themixing chamber 70 from the syringe pump SR2 for diluting the sample 750times for second-stage dilution. Thus, a second-stage diluted sample isprepared. Then, the valves SV16, SV20 are closed. At this time, thesecond-stage diluted sample is agitated by air bubbles in the aforesaidmanner.

[0256] Thus, the RBC measurement specimen is prepared in the mixingchamber 70.

[0257] Preparation of WBC Measurement Specimen (Step S9)

[0258] (1) The valve SV19 is opened, the diluent is sucked into thesyringe pump SR2 from the diluent chamber SC1, and the valve SV19 isclosed. Then, the valves SV20, SV27, SV28 are opened to cause thesyringe pump SR2 to suck 0.02-mL air. Thereafter, the valves SV20, SV27,SV28 are closed. Flow paths are preliminary filled with the diluent.

[0259] The valves SV20, SV26, SV27 are opened, and the syringe pump SR2is operated for suction, whereby the hemolyzing agent is sucked into acharging line CL1 from the hemolyzing agent chamber SC2 and retained inthe charging line CL1. At this time, the suction amount of the syringepump SR2 is determined so that the amount of the hemolyzing agentretained in the flow paths including the charging line CL1 becomes 0.5mL. Then, the valve SV26 is closed.

[0260] The valve SV25 is opened, and the syringe pump SR2 is operatedfor discharge, whereby 1.02 mL of fluid including 0.5 mL of the diluent,0.5 mL of the hemolyzing agent and 0.02 mL of the air is discharged intothe detector 50 via a nozzle 61. Then, the valves SV20, SV25, SV27 areclosed.

[0261] (2) The pipette PT is moved to the upper side of the detector 50,and lowered. Then, the valves SV7, SV20 are opened, and the syringe pumpSR2 is operated for discharge, whereby 0.39 mL of the first-stagediluted sample is discharged into the detector 50 from the pipette PT.Then, the valves SV7, SV20 are closed.

[0262] Thus, 0.5 mL of the diluent, 0.39 mL of the first-stage dilutedsample and 0.5 mL of the hemolyzing agent are present in the first andthird containers 51, 53 of the detector 50.

[0263] (3) The pipette PT is lifted, and the exterior and interior ofthe pipette PT are cleaned in the aforesaid manner.

[0264] (4) The valve SV5 is opened, and the air pump P3 is operated tosupply air into the detector 50 for agitation with air bubbles. Then,the air pump P3 is stopped, and the valve SV5 is closed. Thus, thepreparation of the WBC measurement specimen in the first and thirdcontainers 51, 53 of the detector 50 is completed.

[0265] Measurement of WBC and HGB (Step S10)

[0266] (1) The valve SV18, SV23 are opened. Then, a negative pressure isapplied to the waste liquid chamber WC from the negative pressure pumpP1, whereby the diluent is caused to flow from the diluent chamber SC1to the waste liquid chamber WC through the second container chamber 52of the detector 50. Thus, the second container chamber 52 is cleaned,and the diluent is retained in the second container chamber 52. Then,the valves SV18, SV23 are closed.

[0267] (2) The valve SV24 is opened, and the syringe pump SR2 isoperated for suction, whereby the WBC measurement specimen is caused toflow from the first and third container chambers 51, 53 into the secondcontainer chamber 52 via the orifice 55 in the detector 50 (for about 10seconds). Then, the valve SV24 is closed. At this time, theresistance-type detecting section 503 detects changes in impedancebetween the electrodes 58 and 67, and the control section 500 calculatesthe number of the white blood cells (WBC) on the basis of the detectionresult.

[0268] (3) At the same time, light emitted from the light emitting diode68 is transmitted through the specimen, and the intensity of thetransmitted light of the third container chamber 53 is detected by thephotodiode 69. The control section 500 calculates the amount of thehemoglobin (HGB) on the basis of the detected light intensity. The blankmeasurement of the HGB (measurement of the intensity of lighttransmitted through the diluent) is performed immediately after Step (1)of the WBC measurement specimen preparing operation.

[0269] Measurement of RBC (Step S12)

[0270] (1) The valve SV10 is opened, and a negative pressure is appliedto the waste liquid chamber WC from the negative pressure pump P1,whereby residual liquid in the detector 50 is drained into the wasteliquid chamber WC. Then, the valve SV10 is closed.

[0271] (2) The valves SV15, SV20 are opened, and the syringe pump SR2 isoperated for discharge, whereby the diluent is supplied into the firstand third container chambers 51, 53 via the nozzle 60 of the detector50. Then, the valves SV15, SV20 are closed.

[0272] (3) The valves SV18, SV23 are opened, and a negative pressure isapplied to the waste liquid chamber WC from the negative pressure pumpP1, whereby the diluent is supplied from the diluent chamber SC1 intothe second container chamber 52 of the detector 50 for cleaning thesecond container chamber 52. Then, the valves SV18, SV23 are closed.

[0273] (4) The valves SV1, SV12, SV20 are opened, and the syringe pumpSR2 is operated for suction, whereby the RBC measurement specimen issucked from the mixing chamber 70 into a charging line CL2 and retainedin the charging line CL2. Then, the valves SV1, SV12, SV20 are closed.

[0274] (5) The valve SV24 is opened, and the syringe pump SR2 isoperated for discharge, whereby the diluent flows from the thirdcontainer chamber 52 into the first container chamber 51 through theorifice 55 in the detector 50.

[0275] (6) During this period, the syringe pump SR4 is operated fordischarge, whereby the RBC measurement specimen retained in the chargingline CL2 is ejected from the jet nozzle 56 toward the orifice 55. TheRBC measurement specimen ejected from the jet nozzle 56 is surrounded bythe diluent in the preceding Step (5), and passes as a sheath flowthrough the orifice 55 (for about 10 seconds). Then, the valve SV24 isclosed.

[0276] (7) The control section 500 calculates the number of the redblood cells (RBC), the number of the platelets (PLT), the hematocrit(HCT) and other analysis items on the basis of changes in impedancebetween the electrodes 58 and 67 when the sheath flow passes through theorifice 55.

[0277] Cleaning Operation (Step S15)

[0278] (1) The valves SV10, SV14 are opened, and then a negativepressure is applied to the waste liquid chamber WC from the negativepressure pump P1, whereby residual liquid in the mixing chamber 70 andthe detector 50 is drained into the waste liquid chamber WC. Then, thevalves SV10, SV14 are closed.

[0279] (2) The valves SV15, SV16, SV20 are opened, and the syringe pumpSR2 is operated for discharge, whereby the diluent is supplied into themixing chamber 70 and the detector 50. Then, the valves SV15, SV16, SV20are closed.

[0280] (3) The valves SV1, SV2 are opened, and then a negative pressureis applied to the waste liquid chamber WC from the negative pressurepump P1, whereby the diluent is drained from the mixing chamber 70 intothe waste liquid chamber WC through the charging line CL2. Then, thevalves SV1, SV2 are closed.

[0281] Thus, the cleaning operation is completed. The negative pressurein the waste liquid chamber WC is monitored by the pressure sensor J6,and the negative pressure pump P1 is driven to constantly keep thepressure within a range between 100 and 300 mmHg, preferably between 150and 200 mmHg.

[0282] When the amount of the waste liquid stored in the waste liquidchamber WC reaches a predetermined amount, this situation is detected bythe float switch J7, and the liquid draining pump P2 is driven by thefloat switch J7, whereby the waste liquid is drained into the wasteliquid container 102.

[0283] Characteristics of Liquid Transfer

[0284]FIG. 47 is a detailed diagram of a major portion of the fluidcircuit shown in FIG. 42.

[0285] As shown, the fluid circuit includes a tube-shaped thirdretaining portion (charging line) CL1 with a first opening M1 and asecond opening M2 provided at both ends thereof, a liquid dischargeportion (nozzle) 61, a single syringe pimp SR2 having a first suctionport N1 and a second suction and discharge port N2, a first retainingportion (diluent chamber) SC1 for storing a first liquid (diluent), anda second retaining portion (hemolyzing agent chamber) SC2 for storing asecond liquid (hemolyzing agent).

[0286] Opening/closing valves SV19, SV27, SV26 and SV25 are respectivelyprovided between the first retaining SC1 and the first suction port N1,between the first opening M1 and the second suction and discharge portN2, between the second retaining portion SC2 and the second opening M2,and between the second opening M2 and the liquid discharge section 61,which are connected via flow paths.

[0287] Further, an opening/closing valve SV28 for communicating with theatmosphere is connected to the second opening M2 through the flow paths.The flow paths are preliminarily filled with the first liquid (i.e., thediluent).

[0288] In this arrangement, the following steps are performed:

[0289] (1) The valve SV19 is first opened, and the diluent is suckedinto the syringe pump SR2 from the diluent chamber SC1. Then, the valveSV19 is closed.

[0290] (2) Next, the valves SV28, SV27 are opened, and the syringe pumpSR2 is operated for suction, whereby a predetermined volume (20 μL) ofair is sucked into the flow path to provide an air layer in the thirdretaining portion (the charging line) CL1. Thereafter, the valve SV28 isclosed.

[0291] (3) The valve SV26 is opened, and the syringe pump SR2 isoperated for suction. Whereby, a predetermined amount (0.5 mL) of thehemolyzing agent is sucked from the hemolyzing agent chamber SC2 intothe flow path between the point S and the second opening M2 and thecharging line CL1. Then, the valve SV26 is closed.

[0292] (4) The valve SV25 is opened, and the syringe pump SR2 isoperated for discharge, whereby 0.5 mL of the diluent, 0.5 mL of thehemolyzing agent and 0.02 mL of the air are discharged into the detector50 via the nozzle 61. Then, all the valves are closed.

[0293] With this arrangement, two kinds of liquids such as the diluentand the hemolyzing agent can be quantitatively dispensed by the singlesyringe pump SR2.

[0294] The air layer provided in the flow paths prevents the dilluentbetween the syringe pump SR2 and the charging line CL1 from being mixedwith the hemolyzing agent.

[0295] In this embodiment, the liquid is discharged into the upper-opendetector 50 via the nozzle 61, but may be discharged into a closeddetector or chamber via a nipple (liquid discharge portion).

[0296] Construction of Syringe Pump Unit

[0297]FIG. 48 is a front view of a syringe pump unit PU shown in FIG.42.

[0298] As shown, the syringe pumps SR1, SR4 to be paired are fixed inline to a support plate 601 so as to be opposed to each other. A slidingrail 602 is provided on the support plate 601 parallel to the syringepumps SR1, SR4, and a driving pulley 603 and a driven pulley 604 arerotatably provided on upper and lower portions of the support plate 601,respectively.

[0299] A syringe pump motor STM4 provided on the rear side of thesupport plate 603 causes the driving pulley 603 to be rotatably driven.A timing belt 605 is stretched between the pulleys 603 and 604. Thesliding rail 602 supports a sliding member 606 in a slidable manner. Thesliding member 606 is coupled with the timing belt 605 via a couplingmember 607 thereby to be moved vertically up and down by the syringepump motor STM4.

[0300] Pistons 608, 608 a of the syringe pumps SR1, SR2 respectivelyhave terminals 609, 609 a provided at their distal ends. The terminals609, 609 a are connected to each other by means of the engaging member600, and the engaging member 600 is connected to the sliding member 606.When the syringe pump motor STM4 is driven, the pistons 608, 608 acooperate to move vertically up and down.

[0301]FIG. 49 is a vertical sectional view of a syringe pump SR1. Thesyringe pump SR2 has substantially the same construction as the syringepump SR1. As shown, the piston 608 extends from a lower end portion of acylinder 610 with a cylindrical hollow portion 611 provided therein, andcan vertically be inserted into the hollow portion 611. A suction anddischarge nipple 612 is provided at an upper end of the cylinder 610 forcommunicating with the hollow portion 611, and another suction anddischarge nipple 613 is provided in the vicinity of a lower end of thecylinder 610 for communicating with the hollow portion 611.

[0302] O-rings 614, 615, a seal 616 and a collar 617 employed forsealing a gap between the piston 608 and the hollow portion 611 arefixed to a lower end portion of the cylinder 610 by a cap 618 withinside screws. A cleaning member (sponge) 619 for cleaning an outersurface of the piston 608 is fixed to the cap 618 by means of a cap 620.

[0303] In the syringe pump SR1, a liquid is sucked through the nipples612 and 613 into the hollow portion 611 after the lowering of the piston608, and the sucked liquid is discharged through the nipples 612 and 613after the lifting of the piston 608. On the contrary, the syringe pumpSR4 is operated for discharge and suction in a reversed manner.

[0304] Each of the syringe pumps SR1 and SR2 serves as one flow pathbecause the nipples 612 respectively communicate with the nipples 613through the hollow portions 611. The syringe pump SR1 is fastened to afixing portion 622 by a nut 623. The fixing portion 622 is preliminarilyfixed to the support plate 601 by a screw 621.

[0305] FIGS. 50 to 52 are diagrams for explaining an engagingrelationship between the terminals 609, 609 a of the syringe pumps SR1,SR2 and the engaging member 600.

[0306] As shown in FIG. 50, the terminal 609 fixed to the distal end ofthe piston 608 includes a pair of flanges 624, 625, and the terminal 609a fixed to the distal end of the piston 608 a includes a pair of flanges624 a, 625 a. The flanges 624, 625 are provided at an interval W1, andthe flanges 624 a, 625 a are also provided at an interval W1.

[0307] The engaging member 600 has fingers 626, 627 with their widthsW2, W3, respectively. The fingers 626, 627 are respectively insertedbetween the flanges 624, 625 and between the flanges 624 a, 625 a.

[0308] W1, W2 and W3 have a relationship of W1>W2>W3, for example,W1=2.5 mm, W2=2.4 mm and W3=2.0 mm.

[0309] In this arrangement, when the engaging member 600 is moved in anarrow direction Z1, the finger 626 is first brought into contact withthe flange 625 as shown in FIG. 51 thereby to drive the piston 608 inthe arrow direction Z1, and then the finger 627 is brought into contactwith the flange 624 a as shown in FIG. 52 thereby to drive the piston608 a in the arrow direction Z1. Accordingly, the engaging member 600 isdriven in the arrow direction Z1 in association with the movement of thepistons 608, 608 a.

[0310] In the state shown in FIG. 52, when the engaging member 600 ismoved in an arrow direction Z2, the finger 626 is first brought intocontact with the flange 624 thereby to drive the piston 608 in the arrowdirection Z2, and then the finger 627 is brought into contact with theflange 625 a thereby to drive the piston 608 a in the arrow directionZ2.

[0311] Accordingly, the engaging member 600 is driven in the arrowdirection Z2 in association with the movement of the pistons 608, 608 a.

[0312] Thus, the engaging member 600 and the terminals 609, 609 atransmit a driving force supplied from the syringe pump motor STM4 tothe pistons 608, 608 a with a time lag between the pistons, and then thepistons 608, 608 a start driving vertically.

[0313] Therefore, the syringe pump motor STM4 is prevented from beingheavily loaded simultaneously by static friction between the pistons608, 608 a and the cylinders, so that the syringe pump motor STM4 can beoperated at a reduced capacity. The terminals 609, 609 a are notnecessarily required to be fixed to the distal ends of the pistons 608,608 a, respectively, but may be fixed at some midpoints of the pistons608, 608 a.

[0314] Further, the pistons 608, 608 a are not necessarily required tobe provided in line, but may be provided parallel to each other so thatthe axis of the piston 608 is offset from that of the piston 608 a.

[0315] Still further, the fingers 626 and 627 of the engaging member 600may be respectively set to have the same widths W2 and W3, and theinterval W1 between the flanges 624 and 625 may be smaller than thatbetween the flanges 624 a and 625 a.

[0316] Constructions of Air Bubble Sensors BS1, BS2

[0317]FIG. 53 is a top surface view of an air bubble sensor BS1, andFIG. 54 is a view from an A-A arrow direction in FIG. 53.

[0318] As shown, the air bubble sensor BS1 is comprised of a main body650 composed of a transparent resin such as a polyether imide, a flowpath 651 having an oblong shape in section provided in the main body650, and nipples 652, 653 connected to both ends of the flow path 651.The main body 650 is integrated with a photo-interrupter 654 as shown inFIGS. 53 and 54. The photo-interrupter 654 includes a light emittingelement (for example, a LED) 655 and a photo-receptive element 656 (forexample, a photodiode). An air bubble sensor BS2 has substantially thesame construction as the air bubble sensor BS1.

[0319] When light LT is emitted from the light emitting element 655 tothe empty flow path 651, the light LT incident at an angle of 45 degreesis totally reflected at a wall of the empty flow path 651 as shown inFIG. 54. Accordingly, the light LT does not reach the photo-receptiveelement 656. On the other hand, when light LT is emitted from the lightemitting element 655 to the flow path 651 filled with a liquid, thelight LT passes through the wall of the flow path 651 to reach thephoto-receptive element 656 because of the refraction of the light LTwith respect to the liquid.

[0320] An output from the photo-receptive element 656 is converted to alogic signal (binary signal) of “1” or “2” by a conversion circuit (notshown) provided in the photo-interrupter 654, and outputted as adetection signal of the air bubble sensor BS1. That is, when the liquidflows from the nipple 652 into the nipple 653 through the flow path 651,the air bubble sensor BS1 outputs the signal “0” while the flow path 651is filled with the liquid, and outputs the signal “1” while thephoto-receptive element 656 cannot receive the light LT due to thepresence of air bubbles in the flow path 651. The air bubble sensor BS2operates in the same manner as in the air bubble BS1. For example,GP1AO5E commercially available from Sharp Kabushiki Kaisha can be usedfor the photo-interrupter 654.

[0321]FIG. 55 is a circuit diagram illustrating a signal processingcircuit in which the control section 500 (FIG. 43) judges whether airbubbles are generated by receiving respectively outputs V1, V2 from theair bubble sensors BS1, BS2.

[0322] The drive circuit section 501 (FIG. 43) includes an OR gate 504and a pulse width integrating circuit 505 for integrating periods (pulsewidths) during which the signal “1” is outputted from the OR gate 504. Alogical sum Vp of the outputs V1, V2 (binary signals) from the airbubble sensors BS1, BS2 is calculated to be outputted to the pulse widthintegrating circuit 505. As described above, the control section 500including the CPU controls the drive circuit section 501, and allowsvalves SV13, SV9 to be driven.

[0323]FIGS. 56 and 57 are timing charts illustrating respectively arelationship between a driving voltage DV13 of the valve SV13 and theoutput Vp from the OR gate 504, and a relationship between a drivingvoltage DV9 of the valve SV9 and the output Vp from the OR gate 504.

[0324] As shown in FIG. 56, the driving voltage DV13 is turned on, andthe valve SV13 is driven, whereby the diluent is transported from thediluent container 101 (FIG. 42) into the diluent chamber SC1 (FIG. 42).At this time, where the air bubble sensor BS1 detects air bubbles, theoutput V1 from the air bubble sensor BS1 is represented as a pulsesignal.

[0325] On the other hand, the air bubble sensor BS2 is filled with thehemolyzing agent, so that the output V2 remains the signal “0”. Sincethe output Vp from the OR gate is the logical sum of the outputs V1, V2,the output Vp is represented as a pulse signal shown in FIG. 56.

[0326] The pulse width integrating circuit 505 integrates periods Tduring which the output Vp is changed to the signal “1” within apredetermined time period, and the periods T thus integrated areoutputted to the control section 500. The control section 500 judgeswhether to generate the air bubbles on the basis of an integrated value,and then compares the integrated value with a predetermined value. Atthis time, where the integrated value is larger than the predeterminedvalue, the control section 500 judges that the diluent is nottransported to the diluent chamber SC1. That is, the diluent container101 is determined empty by the control section 500. Thereafter, thecontrol section 500 causes the display section 3 to display the judgmenton the display 3 a. That is, the control section 500 judges that nodiluent is present in the diluent container 101 when the driving voltageDV13 of the valve SV13 is turned on and the integrated value obtainedwithin the predetermined time period is larger than the predeterminedvalue.

[0327] As shown in FIG. 57, the driving voltage DV9 is turned on, andthe valve SV9 is driven, whereby the hemolyzing agent is transportedfrom the hemolyzing agent container 103 (FIG. 42) into the hemolyzingchamber SC2 (FIG. 42). At this time, where the air bubble sensor BS2detects air bubbles, the output V2 from the air bubble sensor BS2 isrepresented as a pulse signal.

[0328] On the other hand, the air bubble sensor BS1 is filled with thediluent, so that the output V1 remains the signal “0”. Since the outputVp from the OR gate 504 is the logical sum of the outputs V1, V2, theoutput Vp is represented as a pulse signal shown in FIG. 57.

[0329] The pulse width integrating circuit 505 integrates periods Tduring which the output Vp is changed to the signal “1” within thepredetermined time period, and the periods T thus integrated areoutputted to the control section 500. The control section 500 judgeswhether to generate the air bubbles on the basis of an integrated value,and then compares the integrated value with the predetermined value. Atthis time, where the integrated value is larger than the predeterminedvalue, the control section 500 judges that the hemolyzing agent is nottransported to the hemolyzing agent chamber SC2. That is, the hemolyzingagent container 103 is determined empty by the control section 500.Thereafter, the control section 500 causes the display section 3 todisplay the judgment on the display 3 a. That is, the control section500 judges that no hemolyzing agent is present in the hemolyzing agentcontainer 103 when the driving voltage DV9 of the valve SV9 is turned onand the integrated value obtained within the predetermined time periodis larger than the predetermined value.

[0330]FIG. 58 is a circuit diagram illustrating another exemplary signalprocessing circuit in which the control section 500 (FIG. 43) judgeswhether air bubbles are generated by receiving respectively the outputsV1, V2 from the air bubble sensors BS1, BS2. In this circuit, aswitching circuit 506 is used instead of the OR gate of the signalprocessing circuit shown in FIG. 55.

[0331]FIG. 59 is a timing chart illustrating a relationship among thedriving voltages DV13, DV9 of the respective valves SV13, SV9, theoutput Vp from the OR gate 504 and the switching operation of theswitching circuit 506.

[0332] As shown in FIG. 59, the driving voltage DV13 is turned on, and aswitch of the switching circuit 506 is switched to SW1, whereby theoutput Vp inputted to the pulse width integrating circuit 505 becomesequal to the output V1. The pulse width integrating circuit 505integrates periods T during which the output Vp is changed to the signal“1” within the predetermined time period, and the periods T thusintegrated are outputted to the control section 500. The control section500 judges whether to generate the air bubbles on the basis of anintegrated value, and then compares the integrated value with thepredetermined value. At this time, where the integrated value is largerthan the predetermined value, the control section 500 judges that thediluent is not transported to the diluent chamber SC1. Thereafter, thecontrol section 500 causes the display section 3 to display the judgmenton the display 3 a. That is, the control section 500 judges that nodiluent is present in the diluent container 101 when the driving voltageDV13 of the valve SV13 is turned on and the integrated value obtainedwithin the predetermined time period is larger than the predeterminedvalue.

[0333] As shown in FIG. 59, the driving voltage DV9 is turned on, andthe switch of the switching circuit 506 is switched to SW2, whereby theoutput Vp inputted to the pulse width integrating circuit 505 becomesequal to the output V2. The pulse width integrating circuit 505integrates the periods T during which the output Vp is changed to thesignal “1” within the predetermined time period, and the periods T thusintegrated are outputted to the control section 500. The control section500 judges whether to generate the air bubbles on the basis of theintegrated value, and then compares the integrated value with thepredetermined value. At this time, where the integrated value is largerthan the predetermined value, the control section 500 judges that thehemolyzing agent is not transported to the hemolyzing agent chamber SC2.Thereafter, the control section 500 causes the display section 3 todisplay the judgment on the display 3 a. That is, the control section500 judges that no hemolyzing agent is present in the hemolyzingcontainer 103 when the driving voltage DV9 of the valve SV9 is turned onand the integrated value obtained within the predetermined time periodis larger than the predetermined value.

[0334]FIG. 60 is an exemplary of another switching circuit which can beused instead of the switching circuit 506 of FIG. 58. A switchingcircuit 507 comprises two AND gates 507 a, 507 b and an OR gate 507 c.

[0335] Where an output from the CPU is the signal “1”, the signal “1” isinputted to the AND gate 507 a and the signal “0” is inputted to the ANDgate 507 b. Therefore, an output V3 from the AND gate 507 a is changedto the signal “1” only when the output V1 is the signal “1”. On theother hand, an output V4 from the AND gate 507 b is changed to thesignal “0” irrespective of the signal of the output V2 from the airbubble sensor BS2. That is, the output Vp becomes equal to the output V1when the output from the CPU is the signal “1”.

[0336] Where the output from the CPU is the signal “0”, the signal “0”is inputted to the AND gate 507 a and the signal “1” in inputted to theAND gate 507 b. Therefore, the output V3 from the AND gate 507 a ischanged to the signal “0” irrespective of the signal of output V1 fromthe air bubble sensor BS1. On the other hand, the output V4 from the ANDgate 507 b is changed to the signal “1” only when the output V2 from theair bubble sensor BS2 is the signal “1”. That is, the output Vp becomesequal to the output V2 when the output from the CPU is the signal “0”.

[0337] According to this invention, the liquid aspirator has theplurality of elongated recesses formed in the outer surface of thehollow pipe thereof. When the liquid aspirator is stuck into the samplevessel with the rubber cap, the inside of the sample vessel immediatelycommunicates with the atmosphere through each of the recesses.Therefore, the sample can smoothly be sucked and quantified through theliquid aspirator, so that analysis accuracy can be improved. At leastone of the recesses can be prevented from being filled with the rubbercap when the liquid aspirator virtually reaches the bottom of the samplevessel. In addition, when the exterior of the liquid aspirator iscleaned, the recesses are cleaned at the same time, and therefore theanalyzer does not need to further provide a cleaning flow system forcleaning the recesses.

What is claimed is:
 1. A sample analyzer comprising: a liquid aspiratorfor aspirating a sample from a closed container; a preparing section forpreparing an analysis sample using the aspirated sample; and ananalyzing section for analyzing the prepared analysis sample; the liquidaspirator including an elongated pipe to be stuck into the closedcontainer, the pipe having a liquid flow path extending therein and aplurality of communicating sections provided in an outer surfacethereof, at least one of the communicating sections communicatingbetween an inside and an outside of the container when the pipe is stuckinto the container.
 2. The sample analyzer of claim 1, wherein theliquid flow path extends parallel to an axis of the pipe.
 3. The sampleanalyzer of claim 1, wherein each communicating section includes anelongated recess provided in the outer surface of the pipe.
 4. Thesample analyzer of claim 3, wherein each recess are provided parallel toan axis of the pipe.
 5. The sample analyzer of claim 4, wherein therecesses are arranged in line.
 6. The sample analyzer of claim 5,wherein an interval between the recesses is smaller than each recess inlength.
 7. The sample analyzer of claim 3, wherein the closed containerhas a cap through which the pipe is stuck into the closed container, thecap having a thickness smaller than a length of each recess.
 8. Thesample analyzer of claim 1, wherein the pipe has a head section taperedtoward a tip thereof, and the tip is positioned on an axis of the pipe.9. The sample analyzer of claim 8, wherein the head section is a pyramidin shape.
 10. The sample analyzer of claim 9, wherein the head sectionis a trigonal pyramid in shape.
 11. The sample analyzer of claim 9,wherein the plurality of communicating sections include elongatedrecesses provided in line parallel to an axis of the pipe, and therecesses are arranged in a straight line extending from one ridgeline ofthe head section.
 12. A liquid aspirator for aspirating liquid from aclosed container, comprising: an elongated pipe having a liquid flowpath extending therein and a plurality of communicating sections;wherein the communicating sections are provided in an outer surface ofthe pipe for communicating between an inside and an outside of thecontainer when the pipe is stuck into the container.
 13. The liquidaspirator of claim 12, wherein the liquid flow path extends parallel toan axis of the pipe.
 14. The liquid aspirator of claim 12, wherein eachcommunicating section includes an elongated recess provided in the outersurface of the pipe.
 15. The liquid aspirator of claim 14, wherein therecesses are provided parallel to an axis of the pipe.
 16. The liquidaspirator of claim 15, wherein the recesses are arranged in line. 17.The liquid aspirator of claim 16, wherein an interval between therecesses is smaller than each recess in length.
 18. The liquid aspiratorof claim 14, wherein the closed container has a cap through which thepipe is stuck into the closed container, the cap having a thicknesssmaller than a length of each recess.
 19. The liquid aspirator of claim12, wherein the pipe has a head section tapered toward a tip thereof,and the tip is positioned on an axis of the pipe.
 20. The liquidaspirator of claim 19, wherein the head section is a pyramid in shape.21. The liquid aspirator of claim 20, wherein the head section is atrigonal pyramid in shape.
 22. The liquid aspirator of claim 20, whereinthe plurality of communicating sections include elongated recessesprovided in line parallel to an axis of the pipe, and the recesses arearranged in a straight line extending from one ridgeline of the headsection.
 23. A liquid aspirator for aspirating liquid from a closedcontainer, comprising: an elongated pipe having a liquid flow pathextending therein and a head section tapered toward a tip thereof;wherein the tip is positioned on an axis of the pipe.
 24. The liquidaspirator of claim 23, wherein the head section is a pyramid in shape.25. The liquid aspirator of claim 24, wherein the head section is atrigonal pyramid in shape.
 26. The liquid aspirator of claim 24, whereinthe pipe includes a first elongated recess provided in an outer surfacethereof, and the first recess is arranged in a straight line parallel toan axis thereof and extending from one ridgeline of the head section.27. The liquid aspirator of claim 26, wherein the pipe further includesa second elongated recess provided in an outer surface thereof, and thesecond recess is arranged in the straight line.
 28. The liquid aspiratorof claim 23, wherein the liquid flow path has a suction port passingthrough a side wall of the pipe.
 29. A sample analyzer comprising theliquid aspirator of claim
 23. 30. A sample analyzer comprising; apreparing section for preparing an analysis sample using a sample; ananalyzing section for analyzing the prepared analysis sample; first andsecond flow paths for transporting liquid to the preparing section;first and second valves for opening and closing the first and secondflow paths, respectively; first and second air bubble sensors forsensing an air bubble in the first and second flow paths, respectively,each air bubble sensor outputting a signal; and a controller forcontrolling the first and second valves so that the valves areselectively opened, wherein the controller judges whether the air bubbleis present in the flow path opened by the valve based on the signalsoutputted from the first and second air bubble sensors.
 31. The sampleanalyzer of claim 30, wherein the controller judges that the air bubbleis present in the flow path when the corresponding air bubble sensorkeeps outputting the signal indicative of the sensed air bubble duringmore than a predetermined time period.
 32. The sample analyzer of claim30, further comprising a display, wherein the first flow path isconnected to a liquid container containing the liquid and the controllerallows the display to display that the liquid container is empty whenthe controller determines that the air bubble is present in the firstflow path.
 33. The sample analyzer of claim 30, further comprising an ORgate for transmitting a logic sum of the signals outputted from thefirst and second air bubble sensors to the controller.
 34. The sampleanalyzer of claim 30, further comprising a switching section forselecting the signals outputted from the first and second air bubblesensors referring to the opened valve to transmit the selected signal tothe controller.
 35. The sample analyzer of claim 30, wherein the firstand second flow paths transport a diluent and a hemolyzing agent as theliquid, respectively.
 36. An air bubble detector comprising: first andsecond air bubble sensors for sensing an air bubble in first and secondflow paths, respectively, each air bubble sensor outputting a logicalpulse signal, the logical pulse signal representing a sensing timeperiod of the air bubble in pulse width; and an integrating section forintegrating pulse widths of the logical pulse signal outputted from eachsensor during a time period.
 37. The air bubble detector of claim 36,further comprising an OR gate for logically summing the logical pulsesignals outputted from the first and second air bubble sensors, whereinthe integrating section integrates pulse widths of the summed pulsesignals during the time period.
 38. The air bubble detector of claim 36,further comprising a switching section for selecting the first or secondair bubble sensor and for receiving the logical pulse signals outputtedfrom the selected air bubble sensor, wherein the integrating sectionintegrates the pulse widths of the received logical pulse signals duringthe time period.
 39. A sample analyzer comprising the air bubbledetector of claim
 36. 40. A sample analyzer comprising: an adaptor forholding a sample container containing a sample; a rack for removablyreceiving the adaptor; a preparing section for preparing an analysissample from the sample; and an analyzing section for analyzing theprepared analysis sample, wherein the adaptor comprises a samplecontainer supporting section for receiving the sample container and areceiving tray for receiving the sample to be spilled from the samplecontainer.
 41. The sample analyzer of claim 40, wherein the receivingtray is provided around an inlet of the sample container supportingsection.
 42. The sample analyzer of claim 40, further comprising: anadaptor detecting sensor for sensing the adaptor to be received by therack; and a controller for controlling the preparing sectioncorresponding to an output of the adaptor detecting sensor; wherein theadaptor comprises a first identity section to be sensed by the adaptordetecting sensor.
 43. The sample analyzer of claim 40, furthercomprising: an adaptor recognizing sensor for recognizing a type of theadaptor; and a controller for controlling the preparing sectioncorresponding to an output of the adaptor recognizing sensor; whereinthe adaptor comprises a second identity section to be sensed by theadaptor recognizing sensor.
 44. The sample analyzer of claim 40, whereinthe rack has a notch for positioning the adaptor, and the adaptor has aprojection to be fitted into the notch.
 45. The sample analyzer of claim40, wherein the rack has a projection for positioning the adaptor, andthe adaptor has a notch to be brought into engagement with theprojection.
 46. An adaptor which is removably inserted in a rack of asample analyzer to hold a sample container containing a sample,comprising: a sample container supporting section for receiving thesample container; and a receiving tray for receiving the sample to bespilled from the sample container.
 47. The adaptor of claim 46, whereinthe receiving tray is provided around an inlet of the sample containersupporting section.
 48. The adaptor of claim 46, further comprising afirst identity section to be sensed by an adaptor detecting sensorprovided in the sample analyzer, the adaptor detecting sensor sensingwhether the adaptor is inserted in the rack.
 49. The adaptor of claim46, further comprising a second identity section to be sensed by anadaptor recognizing sensor provided in the sample analyzer, the adaptorrecognizing sensor recognizing a type of the adaptor.
 50. The adaptor ofclaim 46, further comprising a positioning portion for positioning theadaptor with respect to the rack.
 51. The adaptor of claim 46, whereinthe sample container supporting section receives the sample container tosupport the sample container resiliently.
 52. The adaptor of claim 46,wherein a first recess is provided in the sample container supportingsection, the sample container supporting section comprising a firstresilient member inserted into the first recess and a sample containerinserting section fitted into the first recess and mounted on the firstresilient member, the sample container inserting section receiving thesample container therein.
 53. The adaptor of claim 52, wherein a secondrecess for receiving the sample container is provided in the samplecontainer inserting section, and the sample container inserting sectioncomprises a second resilient member for positioning the sample containerin the second recess.
 54. A sample analyzer comprising: a preparingsection for preparing an analysis sample to be analyzed; and ananalyzing section for analyzing the prepared analysis sample, whereinthe preparing section comprises a syringe pump unit used for preparingthe analysis sample, the syringe pump unit including: a first syringepump having a first cylinder and a first piston to be inserted in thefirst cylinder; a second syringe pump having a second cylinder and asecond piston to be inserted in the second cylinder; a connectingsection provided between the first syringe pump and the second syringepump for connecting the first piston and the second piston; and adriving source for driving the first and second pistons through theconnecting section.
 55. The sample analyzer of claim 54, wherein thefirst and second pistons are arranged in line.
 56. The sample analyzerof claim 54, wherein when the driving source drives the first and secondpistons, the connecting section actuates so that one of the first andsecond pistons starts moving and the other starts moving late.
 57. Thesample analyzer of claim 54, wherein the connecting section comprises: afirst terminal attached to the first piston; a second terminal attachedto the second piston; and an engaging member for engaging the first andsecond terminals, wherein the engaging member is engaged with the firstterminal so as to have a first clearance in a moving direction of thefirst piston and engaged with the second terminal so as to have a secondclearance in a moving direction of the second piston, the firstclearance being smaller than the second clearance.
 58. The sampleanalyzer of claim 57, wherein each of the first and second terminalscomprises a pair of flanges spaced apart in a moving direction of thecorresponding piston.
 59. A syringe pump unit comprising: a firstsyringe pump including a first cylinder and a first piston to beinserted in the first cylinder; a second syringe pump including a secondcylinder and a second piston to be inserted in the second cylinder; aconnecting section for connecting the first piston and the secondpiston; and a driving source for driving the first and second pistonsthrough the connecting section.
 60. The syringe pump unit of claim 59,wherein the first and second pistons are arranged in line.
 61. Thesyringe pump unit of claim 59, wherein when the driving source drivesthe first and second pistons, the connecting section actuates so thatone of the first and second pistons starts moving and the other startsmoving late.
 62. The sample analyzer of claim 54, wherein the connectingsection comprises: a first terminal attached to the first piston; asecond terminal attached to the second piston; and an engaging memberfor engaging the first and second terminals; wherein the engaging memberis engaged with the first terminal so as to have a first clearance in amoving direction of the first piston and engaged with the secondterminal so as to have a second clearance in a moving direction of thesecond piston, the first clearance being smaller than the secondclearance.
 63. The syringe pump unit of claim 62, wherein each of thefirst and second terminals comprises a pair of flanges spaced apart in amoving direction of the corresponding piston.
 64. A sample analyzercomprising: a preparing section for preparing an analysis sample to beanalyzed using a sample, a first liquid and a second liquid; and adetector for detecting a signal from the analysis sample, wherein thepreparing section comprises a liquid transfer unit, the liquid transferunit including: a pump connected to a first liquid retaining section forstoring the first liquid and a second liquid retaining section forstoring the second liquid; a flow path for connecting between the pumpand the second liquid retaining section; a third liquid retainingsection placed in the flow path; and a liquid discharge sectionconnected to the third liquid retaining section; the pump transportingthe second liquid from the second liquid retaining section to the thirdliquid retaining section and discharging the second liquid with thefirst liquid via the liquid discharge section to the detector.
 65. Thesample analyzer of claim 64, wherein the third liquid retaining sectionis tubular.
 66. The sample analyzer of claim 64, wherein the flow pathcomprises: a first flow path provided between the second and thirdliquid retaining sections; and a second flow path provided between thethird liquid retaining section and the pump, and wherein the liquidtransfer unit further comprises: a third flow path provided between thepump and the first liquid retaining section; a forth flow path providedbetween the third liquid retaining section and the liquid dischargesection; and first, second, third and forth valves for opening andclosing the first, second, third and forth flow paths, respectively. 67.The sample analyzer of claim 64, wherein the liquid transfer unitcomprises an air flow path for supplying air to the third liquidretaining section, the pump supplying the air to the third liquidretaining section through the air flow path before transporting thesecond liquid to the third liquid retaining section.
 68. The sampleanalyzer of claim 64, wherein the first liquid is a diluent and thesecond liquid is a hemolyzing agent.
 69. The sample analyzer of claim64, further comprising: a first valve for connecting and isolating thefirst liquid retaining section and the pump; and a second valve forconnecting and isolating the second liquid retaining section and thepump, wherein the first valve is opened and the second valve is closedwhen the pump sucks the first liquid, and the second valve is opened andthe first valve is closed when the pump sucks the second liquid.
 70. Aliquid transfer unit comprising: a pump connected to a first liquidretaining section for storing a first liquid and a second liquidretaining section for storing a second liquid; a flow path forconnecting between the pump and the second liquid retaining section; athird liquid retaining section placed in the flow path; and a liquiddischarge section connected to the third liquid retaining section; thepump transporting the second liquid from the second liquid retainingsection to the third liquid retaining section and discharging the secondliquid with the first liquid via the liquid discharge section.
 71. Theliquid transfer unit of claim 70, wherein the third liquid retainingsection is tubular.
 72. The liquid transfer unit of claim 70, whereinthe flow path comprises: a first flow path provided between the secondand third liquid retaining sections; and a second flow path providedbetween the third liquid retaining section and the pump; the liquidtransfer unit further comprising: a third flow path provided between thepump and the first liquid retaining section; a forth flow path providedbetween the third liquid retaining section and the liquid dischargesection; and first, second, third and forth valves for opening andclosing the first, second, third and forth flow paths, respectively. 73.The liquid transfer unit of claim 70, further comprising an air flowpath for supplying air to the third liquid retaining section, the pumpsupplying the air to the third liquid retaining section through the airflow path before transporting the second liquid to the third liquidretaining section.
 74. The liquid transfer unit of claim 70, wherein thefirst liquid is a diluent and the second liquid is a hemolyzing agent.75. The liquid transfer unit of claim 70, further comprising: a firstvalve for connecting and isolating the first liquid retaining sectionand the pump; and a second valve for connecting and isolating the secondliquid retaining section and the pump, wherein the first valve is openedand the second valve is closed when the pump sucks the first liquid, andthe second valve is opened and the first valve is closed when the pumpsucks the second liquid.